Please don't just think, but look it up.
- Open your WLM contactlist
- If the menubar is not there, press the little button left of the minimize button to make it appear (or just maximize your contactlist window).
- Click on "Help" > "About Messenger".
- Now you see something like "Version X.X (Build X.X.XXXXX)"
- Write the full build number in your post.
Like Supersonicdarky said, Plus! will not run on any WLM 8.1.xxxx version. But, it will also not run on old 8.0 beta builds. However, the current public availible WLM 8.0 works fine with the current Plus! version, download it here:
http://get.live.com/messenger/overview
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