Do not install "Company of Heroes" before installing the "Opposing Fronts" expansion. "Opposing Fronts" has "Company of Heroes" built in. However, you still have to download "Company.of.Heroes-LOADiNG", as you will need it, to install both games.
If you already have "Company of Heroes" installed. Backup any saved games and uninstall it - including removing any "CoH" or "OF" folders in "My Documents" (doing so is the only way to make sure the patches to be installed, will see your installation as valid).
Download "Company_of_Heroes_Opposing_Fronts-FLT" (if you have not already done so). Extract its rar archives (with a extraction software such as "WinRAR") and mount the extracted "flt-chof.iso" (with an emulation software such as "DAEMON Tools").
Install "Opposing Fronts" using one of the two serials given at the buttom in the "flt-chof.nfo" file (when opened with an NFO reader such as "DAMN NFO Viewer"), provided in the "Company_of_Heroes_Opposing_Fronts-FLT" release. Also make sure to uncheck the default checked option on the installer, causing the game to run directly after installation.
Go to "http://www.cohpatch.com/help.html" and install all the patches provided next to "Opposing Fronts 2.1" - being the version you are provided after a fresh install of "Opposing Fronts". Doing so is the fastest way to patch the game, but it still may take some time...
Head over to the directory where you installed "Opposing Fronts", and under "validatorsrs", backup the file rs.dll (if you want to be able to install future patches) and replace it with the rs.dll provided in the folder "Fairlightrs" on the disc you mounted from the "Company_of_Heroes_Opposing_Fronts-FLT" release.
Now here comes the tricky part. Find a crack that matches the latest patch you downloaded (if the latest patch is new, you might have to wait a few days for a crack to be released). The only hint I can provide, is "GCW". Now when you‘ve found one (using my hint or not), you should...
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