Trouble downloading certain addons

I'm able to download only one type of file and that's the PBO and BISIGN files, 7Z and RAR folders never show up or work in my game and I only have one thing to download for the entire addon while the PBO and BISIGN addons have addon and key folders. Is my software the problem or is there a way to be able to download the 7Z and the RAR addons? Thanks!

Do you mean that addons you download that are 7z or rar do not work in ArmA?

If so, did you put the 7z or rar in the addons folder?

7z and rar are compression formats. To use the included addons you have to unpack them first. Compression is used to reduce filesize when up/downloading files. Maybe this is a interesting read.

:EDITH:

Maybe this analogy clears it up: look around you, the room your sitting in with all it's furnitures and you stuff in it. If you're moving, you would pack it up so it takes less space in your car. Arrived at your new location, you need to unpack your stuff first before you can work with it again. That whole pack/unpack stuff is what 7z, rar and zip do. They're just containers for your stuff.

Yea sorry I should have looked harder. I downloaded winrar and it works fine and I can download anything. thanks for the help though. The problem I have now is something that a lot of people are having. I downloaded some addons such as the F/A-22A Raptor which requires Community Based Addon, the problem comes up with an error that a lot of people are having with DayZ "Addon 'cba_xeh_oa' requires addon 'CA_CommunityConfigurationProject_E'. I got a little bit smarter and did some research. A lot of people said to go to properties on DayZ and go to the lastest beta patch. It works for DayZ, but I don't play DayZ as much as ArmA 2, I don't have a beta patch to get rid of it for good like on DayZ. Do I have to get a beta patch for my ArmA 2: CO for steam or is there another way around this so that I don't keep getting these annoying error messages everytime I play. Thanks so much!

---------- Post added at 04:39 ---------- Previous post was at 04:34 ----------

Once I get into the game I get a reoccuring error message of Script ca\communityconfigurationproject_e\ai_madetankgunnersuseatandheammo\muzzle\init.sqf not found. Is this tied with the other error message and would go away if the other one is solved, or is this a whole other error?

Do I have to get a beta patch for my ArmA 2: CO for steam?

Yes you need Beta Patch. Also use Play with six it makes using mods and updating your game lot easier.

That's what english is all about, it only matters if the other person can understand you, and you speak perfect english, writing that is. So beta patch i know i need, is it in armaholic, because i trust armaholic over other websites, I've downloaded an Arma: OA patch before from another website and got a virus. What is play with six besides mods and updating? Thanks for responding so quick!