Okay i understand you want to 'delete' (uninstall) it:
Please try this:
Control Panel > Add/Remove Programs,
It would seem your installer would be corrupted if you used a program to remove it.
To complete this, please visit
http://www.msgplus.net/download.php and download it again.
Reinstall the program.
Control Panel > Add/Remove Programs
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If you are still experiencing problems, please post back the full detail of the error message.