I am wondering how to reinstall simconnect. Do I have to completely uninstall FSX. I have so many add ons I would hate to have to start from scratch again. My simconnect isn't working with FSUIPC. Sometimes it does and other times it doesn't so I am wondering if it corrupt.

You can get simconnect from the 3 FSX SDKs. The individual installer is called simconnect.msi

I have under my programs, Microsoft flight, Microsoft Flight Simulator X, Microsoft Flight simulator X SDK. How do I go about getting the simconnect. I apologize for probably sounding stupid but I really want to try to fix this ongoing problem and I have no idea how to do so. Is it complex?

You need to browse to the SDK folder. If you're not sure what you are doing them it is best to uninstall and re-install FSX. Another thing to try is a Repair install of FSX.