UserLock Documentation
UserLock Documentation

UserLock Frequently Asked Questions

Web Console - HTTP Error 503. The service is unavailable

I get the error message “HTTP Error 503 - Service unavailable” when displaying the UserLock Web console. How do I fix it?
When displaying the UserLock Web Console, the following error message appears:
ERROR 503 – Service unavailable

Service Unavailable

This message is displayed because the UserLockAppPool application pool in IIS failed to start.

Application Pools

And in the Application log in the Windows Event Viewer of your UserLock server, we find the following error:

The Module DLL 'C:\Program Files\Microsoft\Exchange Server\V14\Bin\kerbauth.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.

With “IIS-W3SVC-WP” as source and 2282 as “Event ID”.
This is a known issue on a 64-bit server with Exchange which set default dll to load on all Application pool. UserLock tries to load a dll that it doesn’t need, because Exchange set it as default, and this dll doesn’t exist in 32-bit version.

You can work around this issue modifying these dll loading settings.

  1. Locate and backup the following file:
    %windir%\system32\inetsrv\config\applicationhost.config

  2. In the "globalModules" section, find and modify the following entries by adding preCondition="bitness64" just before "/>" for each line (except if preCondition="bitness64" is already there):

    • "kerbauth" <path/>\kerbauth.dll
    • "exppw" <path/>\exppw.dll
    • On Exchange V15 (not needed on Exchange V14): "cafe_exppw" <path/>\exppw.dll

    For example, on Exchange V15, replace:

    • <add name="kerbauth" image="C:\Program Files\Microsoft\Exchange Server\V15\Bin\kerbauth.dll" />
    • <add name="exppw" image="C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\Owa\auth\exppw.dll" />
    • <add name="cafe_exppw" image="C:\Program Files\Microsoft\Exchange Server\V15\FrontEnd\HttpProxy\bin\exppw.dll" />

    By

    • <add name="kerbauth" image="C:\Program Files\Microsoft\Exchange Server\V15\Bin\kerbauth.dll" preCondition="bitness64" />
    • <add name="exppw" image="C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\Owa\auth\exppw.dll" preCondition="bitness64" />
    • <add name="cafe_exppw" image="C:\Program Files\Microsoft\Exchange Server\V15\FrontEnd\HttpProxy\bin\exppw.dll" preCondition="bitness64" />
  3. In each "isapiFilters" section, find and modify the following entries by adding preCondition="bitness64" just before "/>" for each line (except if preCondition="bitness64" is already there):

    • "Exchange OWA Cookie Authentication ISAPI Filter" <path>\owaauth.dll
    • "Exchange ActiveSync ISAPI Filter" <path>\AirFilter.dll

    For example, on Exchange V14, replace:

    • <filter name="Exchange OWA Cookie Authentication ISAPI Filter" path="D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll" enabled="true" />
    • <filter name="Exchange ActiveSync ISAPI Filter" path="D:\Program Files\Microsoft\Exchange Server\ClientAccess\sync\bin\AirFilter.dll" enabled="true" />

    By

    • <filter name="Exchange OWA Cookie Authentication ISAPI Filter" path="D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\auth\owaauth.dll" enabled="true" preCondition="bitness64" />
    • <filter name="Exchange ActiveSync ISAPI Filter" path="D:\Program Files\Microsoft\Exchange Server\ClientAccess\sync\bin\AirFilter.dll" enabled="true" preCondition="bitness64" />
    With this precondition attribute, these dll won’t be loaded in the 32-bit application pool.
  4. Save and close the file

  5. Restart IIS (run IISRESET command) and relaunch the UserLock Web Console

The UserLock Web Console should now work.
If the same error still occurs, additional modules may require this precondition -- the Application log in the Windows Event Viewer can be used to determine which modules, if any, are causing bitness issues.
Another solution is to change the UserLockAppPool application pool to 64-bit.
We do not recommend you this solution if you use the default Access Database which will not allow you to run report from the web console.