Avast free edition (7) blocking networked computers

[ComputersForLess]

Confirmation from the developer on what?  That changes are made are made to the IRPStackSize registry parameter upon installation?  Don't worry, the developer will confirm this.
It's well documented that major AV software names make these changes upon installation.  Check it out.  Your google works as good as mine does.
I just wasn't aware that Avast did this as well, but now we know.

You can give up on the Revo argument.  That's a dead argument.  My issue is solved, networking is working as it should now, and it was because my registry entry was gone.

When you receive your confirmation you can give the people who come to this forum a hand.  When they have this error you'll know how to help them fix it, since I won't be here.  My problem is solved.

Have a nice day.

[PCGUY#1]

Couple of things to try/consider:  Windows7 default encryption for networked pc's is 128 bit and XP is often 40 or 56.  You may need to lower this setting under advance sharing to 56 bit or 40bit for a windows 7 pc to talk to a windows xp. Also in advance network settingswindows7  turn on network discovery.  (print sharing if you are sharing an attached printer.)
  One other strange quirk if the networked drive was mapped before and its IP address changes on the network it wont work either.

[Tazrunner]

COMFIRMED!

i just went thru my own error checking, and it turns out that this was EXACTLY the problem
i have had AVG installed for years, and no issues. Installed Avast in the last 15 days, and needed my printer for the month end reports and no connection. This IS DIRECTLY RELATED TO AVAST.

Thanks to ComputersForLess, and his very good detective skills, he nailed the issue, and provided a solid fix.

Open your registry editor, (run, regedit) then go to HKEY_LOCAL_MACHINES\System\CurrentControlSet\Services\LanmanServer\Parameters.
Look for the the IRPStackSize entry.  If it's there, modify the value to 16 or higher depending on your use.  I set mine for the max value of 50.
If the entry is not there, (which was my case since Avast deleted it) then create a new one as a DWORD, and make sure your spelling is correct as such: IRPStackSize.
Then modify it again to set the value, (size) at your desired level.
Reboot.
Problem solved.

If it had not been for ComputersForLess, i would have uninstalled Advast and gone on to another AV, and i may still..
Blocking a much needed resource like a network printer is a bad business move Avast! Further more not giving anyway to resolve it thru your own menus is even worse. Forcing one to resolve the issue thru editing their registry -- what are you thinking?

I was testing Avast, as i made a mistake and allowed a virus thru to my system. AVG almost blocked it, but it still got thru. ( i was being hit by and exterior location) I was able to quickly clean it, but i have heard that Avast is a better AV these days. This experience reminds me of getting a virus i think on Norton and NOT being able to DELETE it off of my computer. I want a quality AV that will stop viruses and bots, but then advise me how to remove them, not lock me out of settings that i needed.

Just 2 bits from a frustrated person..