some files could not be scanned

[weihanwang]

I have this problem, and the files that can't be scanned are actually avast's own files, like C:\program files\avast software\avast\defs\11070401\algo.dll or \aswcmnbs.dll or\aswscan.dll or\aswcmnis.dll or\aswcmnos.dll or \aswengin.dll.  I just installed avast today, and this is the first scan I ran immediately after the installation.  Should I be concerned about possibly a trojan?

[Pondus]

files that can not be scanned are just that.....it does not mean they are infected
there can be many reasons why files can not be scanned, password protected or protected by another security program installed.....

if they are all in avast def folder i guess you did a scan right after avast did a cleanup in the def folder..so some files are gone
reboot scan again and i guess it is gone....

[Asyn]

Should I be concerned about possibly a trojan?

No.
Old avast! defintions - Nothing to worry about.

[DavidR]

- Nothing to worry about, those are files in old virus definitions folders and avast is doing some housecleaning to keep the size used on the hard disk to a minimum. This just happens to have occurred between the time you started the scan and it reaching that old defs folder.