Hello,
AVG Firewall is part of paid AVG.
To solve firewall issues, most of the time diagnostic files are needed to analyze the situation.
Please proceed as follows:
1. Download this diagnosis tool:
http://www.avg.com/filedir/util/support/runner_en.exe
2.
Induce the issue multiple times(attempt to scan)
3.
Run the diagnostic tool downloaded in step 1. and continue as per displayed readme.
Note: This procedure of contacting our support is only valid for paid AVG users.
AVG 9 blocks the scanner function on my multifunction printer. I have "safed" the file sharing and printer functions but that doesn't work. Turning off AVG firewall solves the problem. I'm now using the Windows firewall but would rather use the AVG one. How do I solve this problem?

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