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ASP.NET Application Keeps Failing with http Error 503

Hi,
I am working on an ASP.NET application which I am wanting to host on my SBS 2011 box.  It works fine under Visual Studio and the version of IIS that is provided by VS.  I have created a folder for the application called Dashboard in the following folder on the server:

C:\inetpub\wwwroot\Dashboard

I have created the Dashboard folder as an Application that appears under "Default Web Site" in IIS 7.0.
I have created an application pool called "Kohola Dashboard" and assigned the "Dashboard" application to it.

The application uses Dot Net 4.0 and is an x86 32 bit application, it also uses OleDB to store its data in an Access 2003 compatible database. In the application pool advanced settings I have set the "Enable 32 bit Applications" to true and selected .NET Framework version to v4.0. The pipeline mode to Integrated and used a user called "IUser" as the Identity and I have ensured that user does exist and does have permissions to read and write to the C:\inetpub\wwwroot\Dashboard folder and its subfolders.

When I try to connect to it there is a slight delay and then I get an Error 503 and when I check the application pool it says the status is stopped.  Checking the server's System Event logs I am getting a stream of errors like this:

Event 5139 WAS:
A listener channel for protocol 'http' in worker process '11680' serving application pool 'Kohola Dashboard' reported a listener channel failure.  The data field contains the error number.

Event 5139 WAS:
A listener channel for protocol 'http' in worker process '9768' serving application pool 'Kohola Dashboard' reported a listener channel failure.  The data field contains the error number.

Event 5139 WAS:
A listener channel for protocol 'http' in worker process '11740' serving application pool 'Kohola Dashboard' reported a listener channel failure.  The data field contains the error number.

Event 5002 WAS:
Application pool 'Kohola Dashboard' is being automatically disabled due to a series of failures in the process(es) serving that application pool.

Can anyone help with what is causing this and how to stop it from falling over?
Avatar of Dan McFadden
Dan McFadden
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Can you check the error logs in this location?  Path:  C:\Windows\System32\LogFiles\HTTPERR

And post a few lines that show the 503 errors.

Dan
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Dan,
This is the lates HTPErr Log's lines that relate to the errors I am getting:
2016-03-10 01:03:26 fe80::2296:1d4d:25f1:acb0%10 36920 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 01:03:26 fe80::2296:1d4d:25f1:acb0%10 36880 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 02:03:28 fe80::2296:1d4d:25f1:acb0%10 33019 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 02:15:01 192.168.100.51 53844 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:15:40 192.168.100.51 53861 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:16:40 192.168.100.51 53868 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:21:11 192.168.100.51 53898 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:23:53 192.168.100.51 53910 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:24:49 192.168.100.51 53918 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:29:44 192.168.100.51 54108 192.168.100.1 443 HTTP/1.1 GET /dashboard 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:34:40 192.168.100.51 54173 192.168.100.1 443 HTTP/1.1 GET /Dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:36:16 192.168.100.51 54177 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 02:44:25 192.168.100.51 54418 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 03:02:54 76.113.136.98 64269 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 03:06:07 fe80::2296:1d4d:25f1:acb0%10 12222 fe80::2296:1d4d:25f1:acb0%10 80 HTTP/1.1 POST /powershell?PSVersion=2.0 - 1 Connection_Abandoned_By_ReqQueue MSExchangePowerShellAppPool
2016-03-10 03:06:07 192.168.100.40 49512 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 03:06:07 92.40.249.128 65221 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=mary&DeviceId=BTE1RLSOUH3LD4K2U1OCFQ9G4G&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 03:06:07 76.113.136.98 64304 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=shell&DeviceId=8SQU45CG2D4P3EI2B2VBHOFGLC&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 03:06:07 fe80::2296:1d4d:25f1:acb0%10 61245 fe80::2296:1d4d:25f1:acb0%10 80 HTTP/1.1 POST /powershell?PSVersion=2.0 503 1 N/A MSExchangePowerShellAppPool
2016-03-10 03:06:10 192.168.100.40 55037 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 503 1 N/A MSExchangeSyncAppPool
2016-03-10 03:07:09 192.168.100.40 55038 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 503 1 N/A MSExchangeSyncAppPool
2016-03-10 03:07:38 192.168.100.51 54569 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 Disabled Kohola+Dashboard
2016-03-10 03:07:38 192.168.100.51 54691 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 Disabled Kohola+Dashboard
2016-03-10 03:07:38 192.168.100.51 54695 192.168.100.1 443 HTTP/1.1 GET /Dashboard/ 503 1 Disabled Kohola+Dashboard
2016-03-10 03:07:38 192.168.100.51 54797 192.168.100.1 443 HTTP/1.1 GET /dashboard 503 1 Disabled Kohola+Dashboard
2016-03-10 03:07:38 192.168.100.51 54799 192.168.100.1 80 HTTP/1.1 GET /dashboard 503 1 Disabled Kohola+Dashboard
#Software: Microsoft HTTP API 2.0
#Version: 1.0
#Date: 2016-03-10 03:32:07
#Fields: date time c-ip c-port s-ip s-port cs-version cs-method cs-uri sc-status s-siteid s-reason s-queuename
2016-03-10 03:32:07 92.40.249.128 65233 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 03:58:30 192.168.100.40 55045 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 04:32:13 fe80::2296:1d4d:25f1:acb0%10 40867 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 05:03:16 92.40.249.128 65276 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 05:03:21 fe80::2296:1d4d:25f1:acb0%10 35736 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 05:32:10 fe80::2296:1d4d:25f1:acb0%10 40973 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 06:03:55 fe80::2296:1d4d:25f1:acb0%10 10955 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 06:03:55 fe80::2296:1d4d:25f1:acb0%10 10978 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 06:32:14 fe80::2296:1d4d:25f1:acb0%10 57069 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 06:37:54 76.113.136.98 64514 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 07:03:38 fe80::2296:1d4d:25f1:acb0%10 6670 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 07:03:38 fe80::2296:1d4d:25f1:acb0%10 6701 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 07:32:11 fe80::2296:1d4d:25f1:acb0%10 61145 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 07:39:38 92.40.249.128 2677 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 07:52:44 188.29.165.92 38071 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 08:03:21 fe80::2296:1d4d:25f1:acb0%10 47176 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 08:18:42 76.113.136.98 64520 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 08:18:47 192.168.100.51 55923 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 08:18:52 192.168.100.51 55925 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 08:29:59 94.197.121.40 13027 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 08:32:14 fe80::2296:1d4d:25f1:acb0%10 20048 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 08:43:56 76.113.136.98 64522 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 09:03:28 fe80::2296:1d4d:25f1:acb0%10 24714 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 09:08:39 192.168.100.51 55980 192.168.100.1 443 HTTP/1.1 GET /Dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:08:39 192.168.100.51 56365 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:09:00 192.168.100.51 56428 192.168.100.1 443 HTTP/1.1 GET /dashboard 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:10:38 192.168.100.51 56431 192.168.100.1 443 HTTP/1.1 GET /dashboard 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:10:45 192.168.100.51 56439 192.168.100.1 80 HTTP/1.1 GET /dashboard 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:11:17 192.168.100.51 56441 192.168.100.1 80 HTTP/1.1 GET /dashboard 503 1 AppOffline Kohola+Dashboard
2016-03-10 09:31:21 76.113.136.98 64527 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 09:32:11 fe80::2296:1d4d:25f1:acb0%10 63445 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 09:36:51 94.197.121.40 13105 192.168.100.1 443 - - - - - Timer_MinBytesPerSecond -
2016-03-10 09:42:02 76.113.136.98 64529 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 10:03:25 fe80::2296:1d4d:25f1:acb0%10 51950 fe80::2296:1d4d:25f1:acb0%10 80 - - - - - Timer_ConnectionIdle -
2016-03-10 10:07:45 76.113.136.98 64536 192.168.100.1 443 - - - - - Timer_ConnectionIdle -
2016-03-10 10:10:49 fe80::2296:1d4d:25f1:acb0%10 43989 fe80::2296:1d4d:25f1:acb0%10 80 HTTP/1.1 POST /powershell?PSVersion=2.0 - 1 Connection_Abandoned_By_ReqQueue MSExchangePowerShellAppPool
2016-03-10 10:10:49 192.168.100.40 55056 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:10:49 166.170.220.70 44011 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=shell&DeviceId=8SQU45CG2D4P3EI2B2VBHOFGLC&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:11:41 192.168.100.51 57147 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:12:10 192.168.100.51 57154 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:12:19 192.168.100.40 55336 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 503 1 Disabled MSExchangeSyncAppPool
2016-03-10 10:15:25 192.168.100.51 57192 192.168.100.1 443 HTTP/1.1 GET /Dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:16:06 192.168.100.51 57194 192.168.100.1 443 HTTP/1.1 GET /Dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:16:07 192.168.100.51 57198 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:16:39 192.168.100.51 57208 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:20:40 192.168.100.51 57238 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:21:21 192.168.100.51 57242 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:22:26 192.168.100.51 57245 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:22:43 192.168.100.40 55355 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:22:43 166.170.220.70 35243 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=shell&DeviceId=8SQU45CG2D4P3EI2B2VBHOFGLC&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:23:23 192.168.100.51 57254 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:23:50 192.168.100.40 55361 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:24:32 192.168.100.51 57257 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:25:59 192.168.100.40 55363 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:26:01 192.168.100.40 55364 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 503 1 N/A MSExchangeSyncAppPool
2016-03-10 10:26:08 192.168.100.40 55365 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 503 1 N/A MSExchangeSyncAppPool
2016-03-10 10:26:40 192.168.100.51 57262 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:27:45 192.168.100.51 57269 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:28:11 166.170.220.70 37128 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=shell&DeviceId=8SQU45CG2D4P3EI2B2VBHOFGLC&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:28:11 192.168.100.40 55366 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:28:59 192.168.100.51 57285 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:35:43 192.168.100.51 57299 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 Disabled ASP.NET+v4.0
2016-03-10 10:36:34 192.168.100.51 57323 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
2016-03-10 10:37:01 fe80::2296:1d4d:25f1:acb0%10 29390 fe80::2296:1d4d:25f1:acb0%10 80 HTTP/1.1 POST /powershell?PSVersion=2.0 - 1 Connection_Abandoned_By_ReqQueue MSExchangePowerShellAppPool
2016-03-10 10:37:01 192.168.100.40 55367 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?jQAJCBBXgFliktKFf98HBCSOdxkVBGjcWFUDV1A4 - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:37:01 94.197.121.40 13158 192.168.100.1 443 HTTP/1.1 POST /Microsoft-Server-ActiveSync?User=mary&DeviceId=BTE1RLSOUH3LD4K2U1OCFQ9G4G&DeviceType=iPhone&Cmd=Ping - 1 Connection_Abandoned_By_ReqQueue MSExchangeSyncAppPool
2016-03-10 10:37:44 192.168.100.51 57329 192.168.100.1 443 HTTP/1.1 GET /dashboard/ 503 1 AppOffline Kohola+Dashboard
Avatar of Siv

ASKER

I have no ASP.NET errors today but strangely I do have a mass of this kind of error:

Log Name:      Application
Source:        Microsoft-Windows-IIS-W3SVC-WP
Date:          10/03/2016 10:37:43
Event ID:      2282
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      BIGBLUE.sivill.local
Description:
The Module DLL 'C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\Owa\auth\exppw.dll' could not be loaded due to a configuration problem. The current configuration only supports loading images built for a x86 processor architecture. The data field contains the error number. To learn more about this issue, including how to troubleshooting this kind of processor architecture mismatch error, see http://go.microsoft.com/fwlink/?LinkId=29349.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Microsoft-Windows-IIS-W3SVC-WP" Guid="{670080D9-742A-4187-8D16-41143D1290BD}" EventSourceName="W3SVC-WP" />
    <EventID Qualifiers="49152">2282</EventID>
    <Version>0</Version>
    <Level>2</Level>
    <Task>0</Task>
    <Opcode>0</Opcode>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2016-03-10T10:37:43.000000000Z" />
    <EventRecordID>1837220</EventRecordID>
    <Correlation />
    <Execution ProcessID="0" ThreadID="0" />
    <Channel>Application</Channel>
    <Computer>BIGBLUE.sivill.local</Computer>
    <Security />
  </System>
  <EventData>
    <Data Name="ModuleDll">C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\Owa\auth\exppw.dll</Data>
    <Data Name="ProcessorArchitecture">x86</Data>
    <Binary>C1000000</Binary>
  </EventData>
</Event>
Avatar of Siv

ASKER

The above error has led me to this article:

https://blogs.technet.microsoft.com/sbs/2011/04/07/how-to-run-a-32bit-web-application-on-sbs-20082011-standard/

I have therefore modified my applicationhost.config file and deleted the static and dynamic compression on my Dashboard and I am now getting onto my site without the 503 error and the app pool conking out, however instead of starting up as I would expect it is running straight to my custom error page and the error quoted is

"Exception of type 'System.Web.HttpUnhandledException' was thrown."

So it's slightly better but I am not sure why I am getting that?
Avatar of Siv

ASKER

OK, panic over I have figured out the cause of the 'System.Web.HttpUnhandledException'  error now (I had changed the App Pool's user to the ApplicationPoolIdentity whilst trying to figure out what the first issue was and had forgotten to put it back to the IUser who has directory permissions.

Now I have changed it back to IUser all is working again!

Thanks for your help, checking the error in the event logs led me to the OWA error and that led me to the fact that if you want to run 32 bit applications you need to set all the 64 bit Global Module entries bitness to 64 bit and for your 32 bit application you need to delete the Static and Dynamic compression settings.
Avatar of Siv

ASKER

Dan,
Thanks!

Checking for ASP.NET errors in the Application log made me notice a load of errors relating to exppw.dll that is used by Outlook Web App and chasing up that error led me to this article which was the root cause of my problem (I need to run my web application in 32 bit because it uses OleDB in order to read and write to an Access database and this can only run as a 32 bit application).

https://blogs.technet.microsoft.com/sbs/2011/04/07/how-to-run-a-32bit-web-application-on-sbs-20082011-standard/

When I made the changes to "C:\Windows\System32\inetsrv\config\applicationhost.config" file, this fixed the problems OWA was having since I added a 32 bit web application to my IIS. I then as per the above article deleted the static and dynamic compression and my web app then started working properly.