What mod are you running and what version was it built for?
and additionally @ OP, what version of sins are you running?
Most mods out there only work properly with the sins version they were made for (unless someone updates it for a later patch... which will then usually be mentioned in the thread for that mod)... So if you're still using sins 1.05, you can't use joe schmoes Uber-mod for version 1.16 (or vice-versa)