cant enter fgunz

hi guys
so i have a problem with the luncher every time i try to update the game there's a massage pops up that say something like crc invalid and patch
so i looked on the internet and i found that i need to turn off my anti virus and firewall and i did and it didn't help any1 have a idea how to fix it up?

Try uninstalling your anti-virus. After you uninstalled, restart your computer and launch GunZ.

Add gunz.exe to AVG's exception list.