Host_Error: CVEngineServer::PrecacheModel: in CS:S

If you have metamod source installed you maybe experience some problems at the start of a server.
The most common error with the use of models are this:

Host_Error: CVEngineServer::PrecacheModel:

To fix this you only need to remove the metamod.vdf file of the addons folder, and start the server, then you need to restart the server with the metamod.vdf file again to use your plugins.