Popup: Trojan Horse Blocked

Be gentle please- I’m not very technical…

Several Firefox windows open- Yahoo Groups, Ebay, Craigslist & I got a pop-up stating Trojan Horse Blocked. Under that:

Object: Trueffects.net
Infection: JS: Treffuc-A (Trj)
Action: Connection aborted (I don’t think any of my windows were closed)
Process-Program Files\ Mozilla Firefox

I can’t find much on this Trojan, just vague comments implying trueffects.net (whoever that is!) is connected to malware.

What gives? Thanks for any help!

Clean the temp files>>
http://www.geekstogo.com/forum/files/file/187-tfc-temp-file-cleaner-by-oldtimer/
Read instructions on download page before running

Run the Malwarebytes>>
http://www.malwarebytes.org/
Make sure to update before running.

See how that goes, post back.