So you have MSN Messenger 7.5 installed on your computer and you can't remove it. Well, you've tried uninstalling it, so how about manually removing it.
- First check in Task Manager that MSN Messenger isn't running.
[Ctrl + Alt + Del, check in Processes for msnmsgr.exe, End Task if it's running]
- Go to C:\Program Files and delete the folder 'MSN Messenger'
- Then try installing again.
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