When you get this security message again click on :
More informations => Run anyway
Notice : Turn off all antiviruses on your PC to avoiding crashes/updates issues.
If ZClient connected successfully and the problem in all servers, then the problem by your connection, ports closed or smth.
if in 1 server, and another servers are ok, then you just need to open server port on router, i think this can fix it.
For now some launchers have problems because of new updates,
You can try ZloGUILauncher or 34H launcher for that, before trying you just need to redownload Client.zip and extract files into bf3 game root.
or another way [WORKED FOR ME]
Join BF3 servers by Zlo site and try now : https://zloemu.net/servers/bf3
Where did you download it from? What is the source?
Zlo Edition only works using its own servers.
You should have Zlorigin : Click to download
Read FAQ for more informations : Click to read (very important)
ZLOFENIX
Can you detect running programs on his device in the last 24 hours? just to make sure? He may use some cheating, but it is only necessary to confirm before giving him any punishment.
Make sure you have the last Server Files version, Download
Make sure from LauncherServer is connected,
Check your login data, (ZLOGIN, ZPASS) (important)
There is some of instructions here, Check it Check