Error-message "File XYZ.XY version mismatch" appears - what to do?

Sometimes you'll facing an Error-Message in the Format "File XYZ.XY version mismatch" if you try to join our Server. Here is what you can do:

1. Note the file name is mentioned in the Error-Message (simply take a PrintScreen)
2. In the Windows-Explorer (Mac = Finder) find & open the Cache-Folder, you'll find them in common here => C:\Program Files (x86)\Steam\steamapps\common\Red Orchestra\Cache
3. Search for the file "Cache.ini". Open this file in any Text-Editor of your choice (p.e. Notepad / Notepad++ / ..etc..).
4. In this file search for the entry of the file-name mentioned in the Error-Message (p.e. "MaikopT.utx" )
5. Copy (Ctrl + C) that long alphanumeric Key on left side is associated with that file name (p.e. "F19628B54ADA...." )
6. Go back to the Windows-Explorer which should still show your Cache-Folder. Paste the alphanumeric Key in the "Search in Cache" Field (right upper corner)
7. It will show that file now in search resultes - the file has the Format "F19628B54ADA....-1.uxx"
8. delete this file - BUT ONLY THIS FILE 
   
9. Close your Windows Explorer. Your Editor should be still open.
10. Now delete the line, where you found the alpanumeric key and the associated file name from the Error Message - BUT ONLY THIS LINE
11. Don't forget to save the "Cache.ini" before you close your Editor
12. That's it .. 

Don't worry, if you do some mistakes during that procedure, the maximum consequence could be, that you have to delete your Cache-Folder completely. Of course you need not to go through that 12 Points above - you can exactly do that, to delete your Cache-Folder in once completely. The consequence is only, that you, if you join the Server next time you'll will be forced to download again all that stuff you had in your Cache already. Not such doomsday-scenario, cause Internet-Connections are fast nowadays.. except you live at the north-pole..