Hi GokuSpore,
That error message can mean a lot of things; can you please post your launcher log? Then we can find out what the problem is.
Your launcher logs are found in your SWTOR folder under "logs", e.g. "C:\Program Files (x86)\Electronic Arts\BioWare\Star Wars-The Old Republic\logs", and they are sorted by date.
There is another log file called swtor_swtor found in the bitraider folder , this log will be handy as well.
Edit - if you cant solve this error appearing then switch to non streaming launcher per the directions at this link , it is a new game download but the error will be gone
