"Incompatible version"

Whenever my friend and I try to play Eastern Front with each other, we can't connect to each other's games because it says we have"an incompatible version of the game". This cannot be true, as we both have up to date vCoH, as well as the latest Eastern Front patch. Everything is up to date. We are both on Windows 7 64 bit and using Steam.
Thank you!

Neither you or your friend are using custom skin packs or sound packs right?

Make sure both of you have a clean install of EF. Sometimes, old files remain after installing a new version of EF. These remaining files can cause and incompatible version for at least one of you. Did one of you try to connect to other games? If not, please do so in order to find out who's the player with an incompatible version.
After you found that out, make sure to delete every EF file from your Company of Heroes directory and reinstall EF. That should do.
Thank you for playing Eastern Front.

Ahh, I did just find the post here: http://www.easternfront.org/forums/index.php?topic=8001.0 Which talked about having sound packs installed. Thanks guys.
But! Neither of us do have custom sound or skin packs. I do believe that he has another mod (Europe in Ruins) installed alongside EF, however. Would that cause the same issue? Both mods run seamlessly otherwise.
Thank you.

acegard wrote:
Ahh, I did just find the post here: http://www.easternfront.org/forums/index.php?topic=8001.0 Which talked about having sound packs installed. Thanks guys.
But! Neither of us do have custom sound or skin packs. I do believe that he has another mod (Europe in Ruins) installed alongside EF, however. Would that cause the same issue? Both mods run seamlessly otherwise.
Thank you.

This should not cause any issues. Are you both in CoH [IP address redacted]?

Yes we are. All of our mod and CoH versions are up-to-date.

Are you sure you installed the patches in the correct path? You and your friend only have CoH on Steam right? If true, you and your friend should check if someone has a valid path -> "C:\Program Files (x86)\THQ\Company of Heroes".

Does your launcher show the latest version of EF in "About Us"?

Neither of us have "C:\Program Files (x86)\THQ\Company of Heroes", but both EF versions are up to date.