IIS 7 and Above
503 Error Service Unavailable when service is running
Last post Apr 17, 2012 02:59 PM by lperf
Apr 10, 2012 01:24 PM|lPerf|LINK
I have a developer machine with an IIS install. It was working just fine. Not sure what happened in between (I think there was a windows patch installed) but the server stopped responding. I know the service is there, I was able to unistall it and re-install
it and still get the same error when I do http://localhost:
HTTP Error 503. The service is unavailable.
I have also tried with http://127.0.0.1 and same result. I checked the httperr.log file in "C:\Windows\System32\LogFiles\HTTPERR" and all I see is this line:
2012-04-10 13:18:26 ::1%0 53316 ::1%0 80 HTTP/1.1 GET / 503 - N/A -
Which is not very explicit. What else can I check?? Any ideas??
Apr 11, 2012 08:34 PM|lPerf|LINK
Anyone has any ideas on this?
Apr 12, 2012 11:14 AM|Leo Tang - MSFT|LINK
The 503 error means the application pool was stopped. You can start the application in IIS Manager to see if problem resolved.
If the problem persists, please run "eventvwr.exe" open the Window Event Viewer, the description of the event for 503 will help us determine the root cause. Thanks.
Apr 16, 2012 08:56 PM|lPerf|LINK
thanks for your response. Actually the Application pools are running. I can see them in IIS Manager. I also checked the Event Viewer and there is nothing there... I tried to open the server many times with http://localhost and did not log anything there.
I checked the Application node and also Security and System. None shows anything new after I get the error... This is really strange. Anyway, thanks for your help and let me know if there is something else I can do.
Apr 17, 2012 02:10 PM|lPerf|LINK
Anyone has any ideas on this? It is really driving me bananas. I added different application pools, added new web sites with those new application pools and they all do the same thing! Is there something else I need to check? What am I missing?
Apr 17, 2012 02:23 PM|lPerf|LINK
Ok, I figured this much now. I found out that 503 errors are thrown BEFORE the request gets to IIS and that I have to be looking at the HTTP.syslog. I did that and turns out the log has a "N/A" as the reason. After looking at this table for the description
and causes of the problems:
I found that I need to check these parameters to figure out the problem:
Now the question is, how do I check those? Where do I find explanation/settings for those?
Apr 17, 2012 02:54 PM|lPerf|LINK
Ok, I found all of them but this:
The control channel or internal configuration group for the URL is inactive.
I don't know where to check for that. The others were ok. So, if this is true, my guess is then that "control channel" may not be working...
Apr 17, 2012 02:59 PM|lPerf|LINK
Control Channel ---> the port!
My port 80 seems to be occupied by something else and it is creating a conflict somewhere and of course the web site was not coming up... changed the port and it all works... lord...