Problem when uninstall my application in vista and win7, but not in XP

I have a problem when uninstall my application in vista and win7, but not in XP. The error message is " The following error occured on the file 'C:\Windows\system32\mfc40.dll" Access is denied. (0x5)

I made installer for my application using installscr开发者_JAVA百科ipt project in Installshield 2010 if i choose button ignore in that error message, my application can uninstall completed. I cannot found solution for solve that problem. So I try to find another idea,can I bypass that error message using script in installshield, so when get that error,system will ignore that message automatically or the message doesn't appear? Can anyone help me about the script? Thanks in advance.

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Sounds like a UAC issue - you need special permissions to access files in system32.