1. Internal Server Error  Calling LoadLibraryEx on ISAPI filter

Upon opening the WIN-911 Workspace you see the following error:

  • HTTP Error 500.0 - Internal Server Error

    Calling LoadLibraryEx on ISAPI filter "C:\Windows\Microsoft.NET\Framework\v4.0.30319\\aspnet_filter.dll" failed.

A. Cause

IIS is incorrectly trying to load the 32-bit version of the ISAPI filter instead of the 64-bit version of the component.

B. Solution

Modify ISAPI filter mappings for ASP.NET 4.0 to point to the 64-bit version of aspnet_filter.dll.

    1. Open the Internet Information Services (IIS) Manager

    2. Select Default Web Site

    3. In the center pane, double-click ISAPI Filters


    4. Notice the ASP.NET_4.0 entries. There may be three ASP.NET 4.0 entries:

  • ASP.Net_4.0
  • ASP.Net_4.0_32bit
  • ASP.Net_4.0_64bit

    5. Double-click the generic ASP.Net_4.0 entry and set the executable path to                 C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_filter.dll. 

    6. Your system is now configured to use the 64-bit version and the error will no longer appear. 

Technical Support

To create a support case, you will need either your Maintenance Support number or your CD Tracking number. You can create a Case online or contact the product support line: (512)326-1011.