I dunno where you got your Windows Live messenger from but...extension version??? You should download WLMsgr 8.1 from http://get.live.com/messenger
- Which version are you using and which OS?
- Any add-ons, patches etc.?
As this sounds like a virus:
- Have you done an AV scan in safe mode yet?
- Checked for any unknown program(s) in add/remove software?
- Ran anti ad/spyware program?
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