Hello folks,
Some of you maybe heard about my struggle with Bnet Agent to make it work on my 2cond computer.Its been gone 3 weeks now.

I have instaled it on my laptop and worked just fine with no issues, but on the PC desktop...no way!
So my problem was :After running the executable to install the client with the installer, or even running Battle.net from a folder copied from a working PC, starting Battle.net lingers for like a minute then t changes to Updating Battle.net and gets stuck halfway through. If i wait long enough (around 3-4 minutes) I get an error: Whoops! Looks like something is broken etc.
In addition, the installer tends to create multiple instances of Agent.exe in the process tree, which i can't close with end process. It sometimes creates more than 3 copies of Agent.exe.
What i have done :-Deleting Battle.net and Blizzard related folders in ProgramData, ProgramFiles(x86), Appdata and trying to install again.
-Copying these folders from another computer which runs HS normally.
-Using another network or using Google DNS.
-Disabling Firewall/Avast Antivirus
-Cleanup with CCleaner & Malwarebytes
-Deleting Battle.net related registry keys before reinstalling.
-Resetting Internet Explorer settings and proxy settings.
-ipconfig /release and ipconfig /new in cmd.
-winsock reset in cmd.
-Updating Adobe Flash
-Enabling Secondary Logon
-Tried Selective startup
-Tried installing in safe mode
-Tried basically everything in the official troubleshooting pages.
-Replaced the folder in ProgramData with the folder downloded from the manual patching page.
-Firewall, Proxy, Router and Port Configuration: adding TCP and UCP ports
- Battle.net Desktop Application 80, 443, 1119 and 6881-6999 80, 443, 1119, 6881-6999
- Blizzard Downloader 1119, 1120, 3724, 4000, 6112, 6113, 6114, 6881-6999 1119, 1120, 3724, 4000, 6112, 6113, 6114, and 6881-6999
- Hearthstone 1119, 3724 1119, 3724
- World of Warcraft Launcher and Game Client 3724, 1119, 1120, 4000, 6112, 6113, 6114, 80, and 6881-6999 3724, 1119, 1120, 4000, 6112, 6113, 6114, 80, and 6881-6999
Results:Nothing !
SOLVED:Completely deleting Avast antivirus solved the problem.
PS.
I use Avast on my laptop also, and worked from the first time without disable anything and without doing nothing.