Hello there!
GiantSpider has given you great advice, you should follow it.
Messenger Plus! has no virus. But some anti-virus, anti-spyware or anti-adware software incorrectly detect some files as virus or spyware.
Please, when installing Messenger Plus! read carefully each screen, as it crearly tells you it has a sponsor program.
The sponsor program does not harm your system, but if you wish to remove it, follow these steps from this thread =>
How to uninstall ad-ware/sponsor.
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