Your terrain file does not match the version running on this server

[NASAboy3000]

I have this problem but its slightly different. Instead of freezing i am disconnected and a error box comes up saying "Your terrain file does not match the version running on this server."

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[Badspot]

The error tells you exactly what the problem is.  Your terrain file for that map is different than the one on the server.  If this is one of the default maps than either you or the server has modified the terrain file. 

[heedicalking]

The error tells you exactly what the problem is.  Your terrain file for that map is different than the one on the server.  If this is one of the default maps than either you or the server has modified the terrain file. 

I don't know why anyone would start messing with all of the maps.