SBS 2008-SBS2011/OWA, Remote fails with Http Error 500.


Symptoms


Symtopm 1:

Unable to browse Outlook Web Access, or Remote Web work Place / Remote Web Access internall or Externally.

We get the following Errors,

HTTP Error 500.0 - Internal Server Error
Calling LoadLibraryEx on ISAPI filter "C:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll" failed
Module IIS Web Core
Notification Unknown
Handler StaticFile
Error Code 0x8007007e
Requested URL https://mail.contoso.com:443/remote
Physical Path C:\Program Files\Windows Small Business Server\Bin\WebApp\Remote
Logon Method Not yet determined
Logon User Not yet determined

Data Collection:

Enable Failed Request Tracing on OWA / Remote for Error 500. Error in Failed Request Tracing Logs, looks like as shown below.

ErrorDescription Calling LoadLibraryEx on ISAPI filter "C:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll" failed
ModuleName IIS Web Core
Notification 0
HttpStatus 500
HttpReason Internal Server Error
HttpSubStatus 0
ErrorCode 2147942526
ConfigExceptionInfo 
Notification PRE_BEGIN_REQUEST
ErrorCode The specified module could not be found. (0x8007007e)

Symptom 2:

In addition to the above mentioned symptom, on Small Business Server 2011 we are unable to launch the Exchange Management Console or Exchange PowerShell.

We get the following Errors upon Launching the Exchange Management Console.

In Application Logs we get the following Errors.

Log Name:      Application
Source:        Microsoft-Windows-IIS-W3SVC-WP
Date:          9/15/2011 10:13:02 PM
Event ID:      2268
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:     SBS2011.cpandl.local
Description:
Could not load all ISAPI filters for site 'DEFAULT WEB SITE'.  Therefore site startup aborted.

Log Name:      Application
Source:        Microsoft-Windows-IIS-W3SVC-WP
Date:          9/15/2011 10:13:02 PM
Event ID:      2214
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      SBS2011.cpandl.local
Description:
The HTTP Filter DLL C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\owa\auth\owaauth.dll failed to load.  The data is the error.

Cause


The system environment variable "path" does not contain the Exchange bin directory. 

Resolution


 

Use the following steps to resolve the issue:

1.  Open Control Panel

2.  Open the System Icon

3.  Click Advanced System Settings

4.  Click the Environment Variables button

5.  In the Sysem Variables section, edit the variable for Path

On Small Business Server 2011 append the path variable with C:\Program Files\Microsoft\Exchange Server\V14\Bin\

On Small Business Server 2008 append the path variable with C:\Program Files\Microsoft\Exchange Server\Bin\

6.  Restart the Windows Small Business Server

 

More Information


Download Process Monitor from http://live.sysinternals.com

Enable Process Monitor and reproduce the issue.

Search for owaauth.dll

We get the results as shown below.

The process w3wp.exe if trying to look for owaauth.dll which it finds, however it fails to find extrace.dll. This behavior is being exhibited as owaauth.dll is dependant on extrace.dll. Hence the process if looking for extrace.dll in the paths shown above. These locations are being tried as they exists in the environment variable "Path" which does not include the path for extrace.dll

The dependancy of owaauth.dll can be determined using depends.exe.

There are related articles to similar issue.

http://bemis.partners.extranet.microsoft.com/2003867/EN-US

http://bemis.partners.extranet.microsoft.com/2333088/EN-US