To resolve error for Event ID 5009 you can refer steps below.
Possible resolutions include the following:
Use the Debug Diagnostics tool to determine the cause of the crash.
Examine the event log message details for an error number that can provide additional information about the cause of the error. This error number will be different from the Event ID.
For more detailed information, You can refer link below.
I had noticed that July 2018 update cause some issues in IIS and this can be one of those issues.
For testing purpose, you can try to remove this update and check whether it solves the issue or not.
After July 2018 update, some other updates were launched by Microsoft as a solution for some issues caused by this update.
You can try to install those later updates to check whether it helps you to solve the issue or not.
If that not solve your issue then temporary try to remove July 2018 update and wait for the new update to launch.
It is possible that installing the new update helps you to solve your issue.
Regards
Deepak
MSDN Community Support
Please remember to click "Mark as Answer" the responses that resolved your issue.
If you have any compliments or complaints to MSDN Support, feel free to contact MSDNFSF@microsoft.com.
1 Post
Warning Event ID 5009 & 5011, After Jul 2018 windows update
Aug 01, 2018 01:23 AM|Sky Haw|LINK
Window : Window Server 2008 R2 Standard
IIS version 7
After windows update. My company application sometime have problem. Checking Event log found Event ID 5009 & 5011 appeared during the time.


Event ID 5009 :
Event ID 5011 :
Any solution? Thanks
529 Posts
Microsoft
Re: Warning Event ID 5009 & 5011, After Jul 2018 windows update
Aug 02, 2018 02:22 AM|deepakpanchal10|LINK
Hi Sky Haw,
To resolve error for Event ID 5009 you can refer steps below.
Possible resolutions include the following:
For more detailed information, You can refer link below.
Event ID 5009 — IIS Application Pool Availability
To resolve error for Event ID 5011 you can refer steps below.
Diagnose an unresponsive worker process
A worker process that fails to respond may exhibit one of the following symptoms:
For more detailed information, You can refer link below.
Event ID 5011 — IIS Application Pool Availability
I had noticed that July 2018 update cause some issues in IIS and this can be one of those issues.
For testing purpose, you can try to remove this update and check whether it solves the issue or not.
After July 2018 update, some other updates were launched by Microsoft as a solution for some issues caused by this update.
You can try to install those later updates to check whether it helps you to solve the issue or not.
If that not solve your issue then temporary try to remove July 2018 update and wait for the new update to launch.
It is possible that installing the new update helps you to solve your issue.
Regards
Deepak
Please remember to click "Mark as Answer" the responses that resolved your issue.
If you have any compliments or complaints to MSDN Support, feel free to contact MSDNFSF@microsoft.com.
1 Post
Re: Warning Event ID 5009 & 5011, After Jul 2018 windows update
Nov 15, 2018 09:19 AM|treierp|LINK
Good Morning
We got the same problem (Event Id 5011) since august this year.
Do you know the KB-Number of this Patch from the July 2018 Update? We can't find a Patch in July...
Kind Regards
Peter