Hi I had the same problem once XP Service Pack 2 (sp2) was integrated, I got around it by altering the wpi.cmd file as follows; REM Start WPI and wait for its end assoc .hta=hta_auto_file ftype hta_auto_file="%SystemRoot%\System32\mshta.exe" "%%1" start /wait WPI.hta REM call any cleanup code here, or after this script. exit :end This then works fine, seems that something with sp2 changes associations, as Internet Explorer doesnt automatically assign itself as the default browser either! Cheers