So, when I try to load up the Star Wars The Old Republic launcher, it doesn't load up, but it says "Unable to load application configuration". How do I fix this? (By the way, I know nothing about computers)
Right click on the shortcut and choose Properties → Compatibility. Set the compatibility mode to the previous version of Windows (XP SP3 if you're using 7, and 7 SP1 if you're using 8/8.1), and set it to run as Administrator.
Make sure you have the Visual C++ runtime installed (the game includes it under in the install folder under "extras", by default:
C:\Program Files (x86)\Electronic Arts\BioWare\Star Wars - The Old Republic\extras\vc2008redist_x86.exe). You should also install QuickTime and run Windows Update.
Add firewall and antivirus exceptions for
launcher.exe(in the main install folder) and
Reboot and try running the game.
If all that doesn't work, follow the steps here: Why won't my SWTOR Launcher open?