To know if a file is a false positive, please submit it to VirusTotal and let us know the result. If it is indeed a false positive, send it in a password protected zip to virus@avast.com
Please, mention in the body of the message why you think it is a false positive and the password used. Thanks.
Other possibility is JOTTI. VirusTotal and Jotti both have file size limit of 10Mb.
As a workaround, you can add these files to the Standard Shield provider (on-access scanning) exclusion list.
Left click the ‘a’ blue icon, click on the provider icon at left and then Customize. Go to Advanced tab and click on Add button…
You can use wildcards like * and ?. But be careful, you should ‘exclude’ that many files that let your system in danger.
I believe you don’t have to worry about it - it was most likely a temporary file, created for a short while and deleted afterwards - and the ongoing scan for hidden files recognized it as a file hiding itself.
Ok when I saw I had a rootkit I almost cried so it might be a fp? There has been quite a few of those with the stand alone anti rootkit, oh by the way does anybody know what that file name is .swf ?