Something seems to have happened to the "parent forum"; "entropiaforum". I get a message about a missing file, or something like that. (In case it's a virus attack, I wouldn't advice going there until it's cleared up what has happened).
This path works, but the root level gives "Invalid forum path specified! Please edit this file and be sure to include the correct path for your $forumpath variable". No cache in my case since I haven't been there for years. Probably some changes in config files at the hosting.