Please check that your anti-virus/firewall is not blocking the game at all and add any exceptions needed.
You can also try disabling your virus software and test whether the servers then show.
Please also add the following to your whitelist:
- Program Files (x86)\EasyAntiCheat\EasyAntiCheat.exe
- Program Files (x86)\Steam\steamapps\common\Hell Let Loose\EasyAntiCheat\EasyAntiCheat_Setup.exe
- Program Files (x86)\Steam\steamapps\common\Hell Let Loose\Launch_HLL.exe
- Program Files (x86)\Steam\steamapps\common\Hell Let Loose\HLL\Binaries\Win64\HLL-Win64-Shipping.exe
- Program Files (x86)\Steam\steamapps\common\Hell Let Loose\HLL_BugReportUploader.exe
- Program Files (x86)\Steam\steamapps\common\Hell Let Loose\HLL.exe
Try to run HLL.exe as administrator and EAC as not administrator.
Change your Steam region:
Launch Steam - At the upper left corner go to Steam - Settings (a window will pop).
Go to Downloads and change your Download Region to EU, US, or RU (you should choose a country that's closest to your location).
Run the Steam client as an Administrator:
1. Go to your Program Files (x86)\Steam folder
2. Right-click Steam.exe select properties
3. Select the compatibility tab and click run as admin
4. Launch Steam and Hell Let Loose
Turn off IPV6:
1. In the Windows Control Panel, go to Network and Internet, press on Network and Sharing Centre.
2. Press the Change Adapter Settings button, and RMB on the network you are currently using, this could be Ethernet or WiFi, and press Properties.
3. In the following window, disable the IPV6 checkbox and press OK to save the changes, restart your laptop/desktop.
You may need to tick and untick this if it's already unticked.