If the Error after scan was run: Application 4664 - Description Error in aswChestC: Chest AddFile Error 23, is a windows file system error then error 23 = Data error (cyclic redundancy check).
The two errors seem unrelated and the second is one that I wouldn't worry about as for some reason and there could be many the update check failed.
Function setifaceUpdatePackages() has failed. Return code is 0x20000004, dwRes is 20000004.
I have many of these on occasion, but the update process tries again, only start to worry if you get 'hard' errors displayed to the screen on a regular basis, e.g. the Red pop-up window indicating the update failed.
What is the infected file name which was being sent to the chest, where was it found e.g. (C:\windows\system32\infected-file-name.xxx) ?
Check the avast! Log Viewer (right click the avast 'a' icon), Warning section, this contains information on all avast detections. C:\Program Files\Alwil Software\Avast4\ashLogV.exe
- Or check the source file using notepad C:\Program Files\Alwil Software\Avast4\DATA\log\Warning.log and copy and paste the entry.