Hrm...weird. That looks like a bogus message to me. attrib uses a different response when it can't find something...it would look more like this:
File not found - \windows\system32
or it will tell you "Path not found: [pathname]" if you tried running it from another drive. That specific error you wrote is highly suspect.
Go to \windows\system32 and do:
dir /a:h/p
and see if it turns up. if not, then do:
dir /a:s/p
and see if it turns up as well. If it does on EITHER one, do this:
attrib +a -s -h -r winlog*.*
to make it "accessible". If this works, you can manually delete the file with "del".
If NONE of this works, there are other ways. Remote Desktop comes to mind, if you want to try such a route. Regardless, if there's a way to break the system, there's a way to mend it as well, and I've yet to find a piece of malware that I couldn't conquer.