If you're planning on playing ArmA II on the -=MilSim Operations=- server, you'll need to
download one the following addon packs:
MilSimAddonPack_V1.0 [7zip]
MD5_Checksum
MilSimAddonPack_V1.0 [Winzip]
MD5_Checksum
If you want to download the 7zip version you may need to right click and save as ..
I've provided the md5 checksum files so you can verify the archive integrety after downloading.
A nice and easy tool to do so is Kai-Liu's Hash Checker.
You can grab it here:
Kai-Liu's Hash Checker