Issue: I'm currently updating with a service - installing, uninstalling, etc. Suddenly, when I tried uninstalling the service (by the book, using InstallUtil.exe) I get the following error: C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\InstallUtil.exe is not a valid Win32 application. (in the command prompt I even get a message "Access Denied") I looked at the .NET folder, and sure enough, InstallUtil.exe lies there, with size 0 and Date Modified - a few minutes ago !!! Solution: replacing the file with an uncorrupted one solved the problem (lucky for me I have two machines with .NET installed). BE a part of My Network : Thanks & Regards, Rizwan Ahmed Software Engineer And Microsoft Dynamics Technical Consultant Cell Phone:+92 332 3588699 GTalk | LinkedIn | Twitter | Facebook | Blog | Skype