Are you getting this error: (Your map differs from the server's)
You will need to delete the maps you have and re-download the maps.
Here are a few easy steps to guide you through the deletion process.
1. Firstly you need to find Steam in your program files directory/folder.
It should either be in C:\Program Files or C:\Program Files x86. \steam\
2. Once you have got this far, navigate to your team fortress 2 working folder, \steamapps\common\Team Fortress 2\tf\
Most maps download to the download/maps folder.
Scroll down until you see the maps you wish to delete eg:
3. Select them or search for them using the search bar, and press delete, or right click and select delete.
4. Complete, restart team fortress 2
Once you have completed those few easy steps, rejoin the mvm server and it will download the current updated maps for you, and join the game.
Please view the
Machine Attacks thread, for any updates and other map details.