That would explain it (even though, as you pointed out, the ‘only older than 48 hours’ should prevent this from happening).

According to the log, it seems that the avast updater creates a temp folder, and then, when it tries to download some files to it, is doesn’t exist anymore…

Try disabling CCleaner for a while and see if it resolves the problem.

It seems that we could also “fix” this on our side – by creating a file in the folder and opening it so that no process could delete it (and so the folder itself, too).
That’s what we’re doing e.g. in case of the WebShield temp folder.

Thanks
Vlk