just in case this helps i have captured a screen shot of the failed log on in event viewer and the process click here click here
i googled the 'logon process'(two entries for 'advapi.exe' and two entries for 'ms authentication process' at this, time four in total) and found click here for 'advapi.exe'
I'm all up to date with avg virus definitions and program version and scan every time i update it, nothing found after a scan. i ran a on-line scan with third party software as i did before and all is well. spybot, adaware,spywareblaster also up to date, nothing found. i used 'start/search' and only find the google links for 'advapi' nothing else???