Every time that I log into my Mag Pro I am given an error dialog that states: “Internal error! An internal error occurred. For more info see the system log.”
The button for updating virus definitions is greyed out in Preferences.
If I try any sort of scan, I am presented with “error 7012: Communication with Avast Service failed.”
Attached are my system log and a screen shot of one of the error messages from one of the scan screens.
Seems you forgot to attach it. 
Sorry, my bad :-[. Forgot the log file.
Hi,
The relevant parts are missing in the log file, some older log archive (system.log.1, system.log.2, …) is required to see what is going on on your system. Also check, if you have some “com.avast.service” crash reports in the Console and eventually post one of them here.
The system.log.0 file is attached. There are more enumerated 1 though 10 (5, 6, & 7 are missing, though).
The Console tells me “com.avast.helper: Error connecting to service: connect(): No such file or directory” This message is repeated every 10 seconds.