Bug: ArcGISFileHandler.exe - Entry Point Not Found GetProcessImageFileNameW not found in PSAPI.DLL
**This issue has been resolved in ArcGIS (Desktop, Engine, Server) 9.3.1 Service Pack 2.**
After upgrading to ArcGIS Desktop 9.3.1, double-clicking on an MXD document to open it in ArcMap may result in the following error:
"ArcGISFileHandler.exe - Entry Point Not Found GetProcessImageFileNameW not found in PSAPI.DLL"
If documents are opened from the file > open dialog box in ArcGIS Desktop, this error does not appear.
At ArcGIS Desktop version 9.3.1, a new 'file handler' application was created to assist with finding the appropriate application to open map documents. This application relies on a file called 'PSAPI.dll'. If the version of this file is outdated on the machine on which ArcGIS Desktop is installed, the file handler application does not properly associate the map document with ArcGIS Desktop.
To work around this issue, update the file psapi.dll (in C:\WINNT\system32) to version 5.1.2600.2180 or higher.
It is not recommended to change the file association from ArcGISFileHandler.exe back to ArcMap.exe. While changing the file association back to ArcMap.exe can rectify this issue in the immediate term, this workaround can cause problems in the future when upgrading to ArcGIS version 10, which uses the ArcGISFileHandler tool extensively.