Bad Depot?

[Naidanac]

Whenever I try to connect to a multiplayer game I get a message saying "Bad Depot Checksums - Versions Incompatible"

For Single player, on campaign I get errors for these two campaigns:
-El Alamein as Axis
-Operation D-Day as Allies

Whenever I try to load either my game crashes. If you could let me know how to fix either or both of these I would greatly appreciate it.