some map packs are calling on the same script for a certain map... if two maps use the same script and are not named differently they will give this error... there are 1000 maps for cod2 and people use the same scripts alot.... therefore if two servers have this going on it will conflict... giving you this error... the best thing to do for cod2 is to have a folder for each server with according map packs.... so if you wanna play dm... just move your dm maps into the main... if you want to play tdm... move out your dm and move in your tdm... either that or just wait for a error and delete that map pack... and re download when needed...