my ArcSWAT extension in ArcGIS doesn't work anymore

[Emad Mahjoobi]

Hi everybody

I have a hardship with my ArcSWAT extension. It appears in my ArcGIS toolbar but it doesn't work anymore. Despite I reinstall my windows and setup the ArcGIS 9.3.1sp2 and ArcSWAT 2009 Extension again, it exist but doesn't work, it means i click on the "New SWAT Project" in "SWAT Project Setup", but the page of setup project doesn't come.

it should be noted that all of my extensions in ArcGIS is on.

thank you for your help.