Models and Sounds not working online

I have a Gmod server and I installed KCGEORGES Pistol Pack. The weapons went in the server just fine, and I am able to spawn and sell them through dealers. But the Icons in the F4 menu are ERRORS. and the View and World models are also ERRORS, and the sounds do not work. All the weapons do is shoot bullets. Why are they errors? How do I fix it? The only way I know how to fix it is installing it to my own computer, and not relying on the server to install it for me. Please help.