Hello Hookey, Messenger Plus! has
adware bundled in it, but this is optional. When scanning your computer, depending on the scanning software, Messenger plus! is sometimes recognised as spyware or a trojan, this is not the case, there is only adware bundled, so you don't have to install it. The detections are false, the definitions are wrong I'm afraid. It is your anti-spyware program that is wrong, what is the program that you are using if you don't mind me asking? As some programs such as AVG & Microsoft Anti-Spyware detect it falsely.
Even if you did install the adware that is bundled, then it wouldn't cause your computer problems, only add a few desktop icons, a toolbar to Internet Explorer and produce popups.
For more information you can see any of the following threads/websites:
Microsoft's Anti-spyware Software...
Microsoft® Windows AntiSpyware (Beta)
Sponsor, toolbars, and auto-updates
www.mpsupport.net
www.msgstuff.net
