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yfsosj does seem like a random entry. This is suspicious as malware will often create random entries. I don't know what this entry is, however you could experiment by deleting it and see what happens.
Unchecking it from the startup menu will not remove it. I think it would be better to remove it, and whatever has caused it. I would recommend following the Preparation Guide to posting a High Jack This log. You may not need to actually post a log, however. If you follow the instuctions in the Prepatory Guide faithfully then this little bugger ought to be removed. However, rarely is a computer infected with only one thing.
If after completing all of the steps in the Preparation Guide you continue to have issues, post a HJT log as instructed in the Preparation Guide.
Edited by Albert Frankenstein, 02 April 2006 - 10:31 AM.