Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error [Answered]RSS

29 replies

Last post Nov 20, 2012 01:57 PM by EmanuelV

  • Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 09:04 AM|kheang|LINK

    Hi,

    I am getting an intermittent error:

    There is a problem with the resource you are looking for, and it cannot be displayed.

    I did everything I could think of and also went through everything I read online about this type of error and nothing worked so far.

    Not the php settings, not the permissions I am also using the windows installer which configured everything using recommended settings.

    I even checked environment variables to make sure everything is ok.

    I also, did all windows updates to make sure nothing missing or that needed an update would cause the problem.

    The issue is this, I get a 500 error when calling a script that does a number_format(0) with another line of code that queries a database using ODBC link (Acomba) which is an accounting software.

    The page loads fine one time then the 2nd refresh causes a 500, and its always like that, on every 2 refresh.
    When calling number_format(0) alone, it causes a 500 but less often than with the query.

    I have no errors in my error logs, I made sure it could write to the log by doing a simple test.

    I configured a trace in IIS to see what it says and this is what I get:

    This is the event error msg:

    Faulting application name: php-cgi.exe, version: 5.3.8.0, time stamp: 0x4e537f4b
    Faulting module name: KERNELBASE.dll, version: 6.1.7601.17651, time stamp: 0x4e211319
    Exception code: 0xc000008e
    Fault offset: 0x0000b9bc
    Faulting process id: 0xb00
    Faulting application start time: 0x01cc76023c0209a8
    Faulting application path: C:\Program Files (x86)\PHP\v5.3\php-cgi.exe
    Faulting module path: C:\Windows\syswow64\KERNELBASE.dll
    Report Id: 79f5fec0-e1f5-11e0-a6ed-bc305bd47266

    This is what I get from the trace error log

    ErrorDescription C:\Program Files (x86)\PHP\v5.3\php-cgi.exe - The FastCGI process exited unexpectedly
    <div class="content-container">

     

    ModuleName

    FastCgiModule
    Notification 128
    HttpStatus 500
    HttpReason Internal Server Error
    HttpSubStatus 0
    ErrorCode 3221225614
    ConfigExceptionInfo
    Notification

    EXECUTE_REQUEST_HANDLER

    </div>
    <div> </div>

    Just so you know, we tried PHP 5.3.6 before this and we are getting the same error.
    We also tried PHP 5.2.17, this one works, the issue is that the numbers are messed up, we keep getting .: on certain numbers when rounding.
    E.g. ceil(28.08) returns 28.:

    This seems corrected in 5.3.8.

    We also have another server running Windows server 2008 R2 and it also gives the same error when installing PHP 5.3.8

    If anyone has any idea on what could be causing this problem, please let me know, we are desperately trying to fix this issue to get passed it.

    The only other solution we have is overriding the number_format function to skip the 0.
    But we have no idea if there are other issues that would cause it to fail with a 500 error,

    FastCGI IIS7 error 500 windows server 2008

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 09:34 AM|HCamper|LINK

    Hi,

    Have you looked at http://forums.iis.net/t/1179534.aspx thread for FastCGI?

    So which guides "I read online about this type of error and nothing worked so far." did you find ?

    The common problems can fixed and checked with the PHP Manager.

    Do you have the Visual Studio 2008 runtines installed ?

    Martin

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 09:44 AM|kheang|LINK

    I googled and look at a lot of posts that spoke of IIS 7 and 500 errors.

    I checked the php.ini configurations, but I am using the windows installer so it sets it up according to what should be by itself.

    I am not using open_basedir.

    I have switched off logging.

    I have looked at the permissions for the PHP folder, they are ok, even if I add the IIS_IUSRS, it doesn't change anything.

    I even checked in the registry, set the correct path to my PHP.

    PHP manager has no problems or issues with my configuration.

    I have Visual C++ 2008 Redistributable 9.0.21022 and 9.0.30729.6161 installed.
    Is this the same as the visual studio 2008 runtimes? if not, can you provide a link maybe, so I am sure which ones I need.

    The error so far happens on number_format(0) or number_format(0.00) but other numbers seem to work, I haven't tried all numbers.
    When I do echo sprintf("%01.2f", 0), this works.

    I tried running the script command line and browser, only on the browser does it return a 500 error, on the command line, it works fine without ever giving me a 500 error.

    Oh btw, I tried PHP 5.2.17 and it worked fine using FastCGI. But I get a number problem which is like the one mentionned here:

    https://bugs.php.net/bug.php?id=47304 and https://bugs.php.net/bug.php?id=49764

    This is why I am trying to get 5.3.8 working.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 09:59 AM|HCamper|LINK

    Ok,

    Then check that the Recycle settings are correct use this http://learn.iis.net/page.aspx/765/improve-php-error-messages-in-iis-7/ to

    Enable PHP Error Display.  The Visual Studio C++ 2008 is the Runtime VC9 plus the latest patchs and updates.

    Check that your using Dot Net Framework version 2.0 and "Classic" mode http://learn.iis.net/page.aspx/624/application-pool-identities/ for

    the PHP sites.

    Have you checked the php-error.log ? The "default" php.ini does not display errors in the Browser and you may find

    the php-error.log has information that will help ie extensions problems and Time / Zone settings etc.

    Does the PHP Manager phpinfo test match the php.ini settings ?

    Martin

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 10:34 AM|kheang|LINK

    The recycle settings are ok, I pointed it to the php.ini.

    "The Visual Studio C++ 2008 is the Runtime VC9 plus the latest patchs and updates."
    I am running Windows Server 2008 R2 Standard with Service pack 1 and all updates installed.
    Other than that, I have the 2 redistributable visual c++ 2008 installed I mentionned in my previous post.
    Is that ok? Or are there other files I need to install that I do not know of and that do not appear in the windows update?

    There is nothing in the php error logs. As I stated before, I did tests to make sure my errors would appear fine in the logs and they do, so my simple script does not return errors to the logs.

    The phpinfo in both php manager and ini settings match. It even points to the correct php.ini in the loaded configuration file.

    Also the not net framework is 2.0 and classic like you stated for the phppool

    I also wanted to add that I followed the instructions for the improving php errors and I did what it mentionned but it still gave me the normal 500 error msg. So nothing changed at that point.

    Oh and thanks btw for giving me tips, I really appreciate it.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 10:52 AM|HCamper|LINK

    Hi,

    Could you visit the PHP for windows archive http://windows.php.net/downloads/releases/ 

    and download the tests http://windows.php.net/downloads/releases/php-test-pack-5.3.8.zip and

    run some of them ?

    You only have the two "I have the 2 redistributable visual c++ 2008 installed" so that means the intel X86 and Amd X64.

    I suggest visit the Microsoft Download Center and Download the VS 2005, VS2005 SP1, VS 2008 SP1 ,VS 2008 ATL 

    and get the intel X86 and amd X64 versions and install them. After the collection has installed check Windows Update for either

    offers to install latested patchs or they have been installed. The sizes are on avgerage 2 - 4 megs so that hope full is not an issue.

    I find that when installing a System one of the things that helps is install all the Visual Studio Runtimes at one time.

    Martin

     

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 11:15 AM|kheang|LINK

    Ok,

    I installed Microsoft Visual C++ 2005 SP1 and Microsoft Visual C++ 2008 SP1 (both X86 and X64).
    I did all updates for them also.

    I didn't install Microsoft Visual C++ 2005 and 2008 because windows server 2008 R2 isn't in the list of supported OS.

    I still get the same error.

    I am rebooting it to see if it changes anything. Nope no changes.

    Should I still install the 2005 and 2008 even if they don't list windows server 2008 R2 as supported?

    For the test pack what do I with it? I see a bunch of files, do I simply go to one of the tests folder and run any php file?

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 12:24 PM|HCamper|LINK

     Hi,

    Sorry that Runtimes have not fixed the Problems on to the next.

    kheang

    Ok,

     This is good "I installed Microsoft Visual C++ 2005 SP1 and Microsoft Visual C++ 2008 SP1 (both X86 and X64).
               I did all updates for them also."

    Do not worry about "I didn't install Microsoft Visual C++ 2005 and 2008 because windows server 2008 R2 isn't in the list of supported OS.

    I still get the same error. This is bad still :(.

    I am rebooting it to see if it changes anything. Ok. Yes, Many times a reboot helps.

    Should I still install the 2005 and 2008 even if they don't list windows server 2008 R2 as supported? No, Windows the System Detection is correct.

    For the test pack what do I with it?  First "Unblock" the ZIP file then unzip unarchive to a folder called tests. 

    I see a bunch of files. Yes, The tests are the ones used by the PHP builders to check for issues and are standard tests.

     Do I simply go to one of the tests folder and run any php file? No, You can create a folder in IIS Server and copy some of tests from the

    folder you created before.

    Then in IIS Manager use PHP manager to set the php settings.

    Then try the tests from the folder  first at command prompt using the PHP.exe then from the Browser address bar and localhost

    Example: http: // localhost / tests/ test1.php   <- Name may be different.

    Ten post what the results were for command prompt and in the IIS Server . 

    Thanks,

    Martin

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 12:52 PM|HCamper|LINK

    Hi,

    Your PHP 5.3.8 that you installed  is it the Non-Thread-Safe

     http://windows.php.net/downloads/releases/php-5.3.8-nts-Win32-VC9-x86.zip ?

     If you installed the PHP 5.38  thread safe version  it might explain some of the problems.

    Martin

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 01:10 PM|kheang|LINK

    We installed the non thread safe version.

    Currently I tried this installer to get it running with the correct configurations.

    http://www.microsoft.com/web/platform/phponwindows.aspx

    And in my phpinfo it says thread safety disabled.

    I don't know if it helps but it really seems like the number_format(0) alone in a script causes the crash.
    It doesn't crash as often as when I put it with my database query but it seems to do it anyway.

    It just pisses me off that there is not a lot of information regarding the crash or at least information that I can use to find out what's causing it.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 01:22 PM|HCamper|LINK

    Ok,

    Just needed to make sure.

    Yes, "Really seems like the number_format(0) alone in a script causes the crash."

    That does narrorw things down that was the whole point of the test pack.

    If you you really want to find more about the

    Crash information.

     Tess http://blogs.msdn.com/b/tess/archive/2010/09/30/debug-diag-1-2-beta.aspx has links to the Debug Diags

    and lessons for "Crash" Dumps and how to find what is going an.

    Beaware Debugging is not for the Faint of heart and it be time consuming.

    I think it might be better to check the PHP net Web Site and check the Bug List and report the problems.

    Martin

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 01:56 PM|kheang|LINK

    Thanks for your help so far.

    I have produced a crash hang report and I would appreciate if anyone can look at it and tell me if they can figure out anything from it.

    To me it's totally jibberish.

    I have already opened a bug report on PHP.

    Here is the link, if anyone wants to add to it, or if they are able to reproduce the same error.

    https://bugs.php.net/bug.php?id=55712

    I will attach the same crash hang report on the bug page to see if anyone has any ideas.

    Here is the link to the report: http://www.mediafire.com/?ezxjt68v0axozif

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 04:01 PM|HCamper|LINK

    Hi,

    Lets review what's going on with this system

    " Windows Server 2008 R2 amd X64" with "IIS 7.5" using  "PHP version 5.3.8 Non Thread Safe" and "FastCGI'

    and  your getting fatal error 500 from  number_format function.

    The Acomba  Software  requires  dlls that have been added to the PHP Extensions and the php.ini settings ?

    Then it is likey the dlls were not built for X64 so you should change the Bitness settings shown below.

    %windir%\system32\inetsrv\appcmd.exe set config -section:system.applicationHost/applicationPools -[name='DefaultAppPool'].enable32BitAppOnWin64:true

     

    You can also change the settings in the IIS Manager http://learn.iis.net/page.aspx/624/application-pool-identities/ 

    "Configuring IIS Application Pool Identities" in the Dialog it shows enable32AppOnWin64 to true which will match

    the appcmd operation.

    Martin

     

     

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 18, 2011 04:09 PM|kheang|LINK

    Hi,

    Thanks for the tip again.

    I just checked and it is already set to TRUE.

    Acomba is an accounting software that has a database, it's ODBC drivers has already been installed and a link can be established with the odbc_connect function.

    Without the number format 0, the query works fine standalone, it is as soon as both are introduced that an error occurs, and only on number format 0 also. This is very odd.

    It works fine on version 5.2.13 and 5.2.17 but both these versions are no longer supported and have a number issue that I mentionned before which is only fixed in the upgrades.

    This is so frustrating.

    Thanks again.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 03:36 AM|HCamper|LINK

    Hi,

    I checked the PHP bug report you posted: I also looked at the report this is not going to be an easy fix.

    You should forward the report to Vendor Support Staff your likey not alone for this issue.

    I do not see that this is going to be fixed in a short period of time: the Short Answer.

    You may need to use the first suggestion from the PHP Net and the Eng. for changing the code sorry if that is a problem.

    The long version of the Answer: 

    So you can plan your time and understand how things work with Bugs like this:

    So far the PHP Engine is working AFAIK  you might do a few more tests on your system for other types of PHP Code and Functions.

    A) The crash was not security related be happy for small favors.

    B) The crash dump you created requires a Field Engineer  test  the code you have trace where the problems are occuring.

    Example: Trouble Shooting & Testing the 500 errors with Code  http://support.microsoft.com/?id=311766 .

        Note: The above  process takes time & money for all stake holders( PHP Project Developers Users  Engineers ) .

    C)  If the crash dump and testing lead to a possible patch you may receive this to correct the problems. Again Time & Delays.  

    So finally if your waiting for a fix / patch to arrive in a short time you should plan that is not the case sorry.

    I just figure you need to know the time and limits so you can Plan what to do next,

    Martin

     

     

     

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 08:33 AM|kheang|LINK

    Thanks for your help so far.

    I just wanted to add that on another server which runs Windows server standard FE (2008) service pack 2, we have the same error with IIS 7 + PHP 5.3.8 on FastCGI and calling number_format 0 with that ODBC query.

    I looked at the event and that one was the same as the one in this issue except the DLL was different it was kernel32.dll insteald of kernelbase.dll.

    We are going to look into modifying our code at the moment to see if we can bypass it and hope we do not land on another problem that causes a 500 error.

    If anyone out there with the same server and setup could test also see if they get the same error, we could at least make sure it's not just our setup.

    Thanks for everything so far!

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 05:48 PM|kheang|LINK

    I tried installing IIS 7 + PHP 5.3.8 using the windows installer and configured it using recommended settings on my windows 7 workstation.

    I did the test I am trying to get to work and I get the same error.

    This is what I get in the details of the trace I get, does it mean anything?

    "The extended attributes are inconsistent"

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 06:03 PM|HCamper|LINK

    Hi,

    The "Entended Attributes are inconsistent" does mean some thing and it is not good.

    A Search via (Google) is getting this type of result.

     http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/extended-attributes-are-inconsistent/613a4663-9e0c-4dd0-b7df-f2a8ba15fdd0 

    You have problems and not just with PHP from  the looks of things.

    Martin

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 06:25 PM|kheang|LINK

    Yeah that's what I am looking at, but mind you this error is only happening on my windows 7 workstation.

    On the windows server 2008, it is not the same error.

    On the server the errorcode is 4294967295.

    On my workstation it is 255.

    But both crash on the same scenario. Which is odd.

    In the link you pasted, I did the scan like they said and it didn't find anything wrong.

    I am assuming that this error depending on what is happening does not necessarily mean that specific situation, since that one refers to windows explorer crashing and our case is the php-cgi.exe fastcgi, it could be totally unrelated.

    I do know that if you google that error with php-cgi you find some posts talking about it.

    I found someone having a similar issue but had no answers so I asked to see if he had any luck resolving it.

    If anyone has any idea on what else we can try, it could be something simple that is missing.

    So far no luck.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 19, 2011 06:46 PM|HCamper|LINK

    Hi,

    The bad part is with your Windows 7 Workstation back-up you work and important information

    you have to do repairs to the Windows Operating system. You need to plan for the worst.

    The Windows Server 2008 does not have ( Pray or Screen at the Gods OEMS)

             a need for repairs to the WIndows Operating System.

    Yes, The same error on ( two Systems)  you also have Muitpoint Failures that is why Field Enginners

    have a hard time tracking down the root cause. Again Time and Money.

    Sorry your loosing Time + More Time = Money.

    Martin

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 20, 2011 07:33 PM|HCamper|LINK

    Hi,

    So have you backed up the Windows 7 System and started repairs ?

    Martin

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 21, 2011 07:50 AM|kheang|LINK

    Hey,

    No because I am not convinced that my windows 7 system has any problems.
    We have asked a local expert in IIS/PHP installation to take a look at our servers that have that issue and see if he can figure out the problem.

    Since the windows 7 system is my personal machine, it doesn't really matter even if it could be a system issue as the main concern is on my server machines. So we put the focus there.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 21, 2011 08:16 AM|HCamper|LINK

    Hey Back,

    Glad you have local expert to check things. I can only offer suggestions based on  the information provided errors etc..

    Agreed your the one to decide what to focus on what to do next.

    Martin

     

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 21, 2011 11:43 AM|kheang|LINK

    So far from what our expert can tell us, it seems between PHP 5.2.13 and 5.3.8 there have been a lot of changes in the math.c library of PHP which could explain this crash.

    He is still doing more research and will keep me posted.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 25, 2011 05:30 PM|kheang|LINK

    Ok so here is an update.

    From what our conclusion was, is that number_format was to be avoided.

    So we made our own function to use in this case.

    We ended up with another error, in the same area.

    Now it was no longer number_format since we removed it, but round itself.

    So round(0) doesn't work.

    This is beginning to be ridiculous but we are bypassing that also to see if we encounter any other problems in that area.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 26, 2011 09:56 AM|HCamper|LINK

    Hi,

    Thank you for the updates and status and hope for a succesful patch or fix.

    Your problem(s) crashes for Math Libraries in PHP are being handled by experts there is nothing more the IIS Net Forum

    or I can offer to help with this.

    The only other  suggestion  at this point is open up a case with Microsoft Support to match PHP net

    Bug Reporting .

    Regards,

    Martin

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Sep 26, 2011 01:38 PM|kheang|LINK

    Hi,

    Yes that is exactly what I did, on reporting the new find to php.net I believe they are going to be taking at look at this more seriously.

    Hopefully it will be fixed and should help out anyone else experiencing the same problems.

    Thanks.

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Feb 01, 2012 11:01 AM|HCamper|LINK

    Hi Kheang,

    Sorry for being late for replies and checking the

    status https://bugs.php.net/bug.php?id=55712 PHP bugs.

    Have you upgraded from  PHP 5.3.8 to PHP 5.3.9 and the

     latest release http://forums.iis.net/t/1186168.aspx PHP update to 5.3.9 ?

    You have worked with PHP bugs and reports http://forums.iis.net/t/1176586.aspx "Are we dead..."

    can you review the posts and the thread and offer some input to the chat

    from your understanding.

     The thread and chat needs a community member one who has had real world experinces.

    TIA,

    Regards,

    Martin Rasch

     

     

     

     

    Windows and Linux work Together IT-Pros
    Community Member Award 2011
  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Feb 01, 2012 03:34 PM|kheang|LINK

    Hi Martin,

    Thank you for letting me know about PHP 5.3.9.

    To be honest we haven't done anything since the reply from PHP.

    Since the database we are using via ODBC isn't supported by PHP and the database support team don't support PHP we are kind of stuck with this problem.

    So instead of upgrading we stayed with the version we have which has a bug with float numbers, and to bypass that we had to basically avoid problematic numbers.

    So yeah, I will look into it and consider upgrading or at least doing the test, but it would be such a waste of time to encounter the same issue again yet with another upgrade.

    But thank you for checking up on this issue, i appreciate the heads up and your interest!

    I have read the post you mentionned unfortunately I am not really an expert in PHP and windows servers, I just know enough to get around but I don't even know what wincache is or is used for, hopefully they will have more luck in solving their problems than us!

    Thanks gain!

  • Re: Windows Server 2008 R2, IIS7, FastCGI + PHP 5.3.8 - 500 error

    Nov 20, 2012 01:57 PM|EmanuelV|LINK

    I don't know if it will help someone but I had the same error: a 500 error showing only to Internet Explorer user. About the same config as yours but PHP 5.3.13 and IIS 7.5 instead.

    1. In IIS Manager double-click the Page Error settings for your website (the icon shows a little '404' with an exclamation mark)

    2. Check if errors are local or inherited. They should all be inherited (translated from french, don't know the exact term in english)

    3. You can change the setting back by opening the web.config file (at the root of your site) and find a line about errors handling. Remove the lines to fix the problem.

    I could not change that settings from the manager, only from the web.config file.

    Hope it helps.

    EDIT: depending on your permissions sometimes you need to open the web.config as administrator. For that I right-click on my text editor program icon, choose Run as administrator and from the text editor I open the web.config.