Error code 7 usually refers to a compatibility issue..
That said for things to work one day then not the next can be frustrating but I have managed to get Swtor to work on all forms of machines that I have had to work on.
Rule #1 Firewalls Firewalls Firewalls, nothing there is going to be your friend so stay on top of them its 20 seconds work when they play up.
Rule #2 Keep it Simple; Overlays cause more headaches then having a pop up that says Billy is now online or is talking is every going to be worth.
Rule #3 Logs Logs Logs, Save yourself real world time and get into the groove of checking your logs first before spitting the dummy they will give you a good idea where to go first.
**All that said folks can you please provide your Logs, DXdiag + Launcher is always nice, client_settings.cfg is also another one to be familiar with.
I have a Dentist appointment shortly but will get started on a few walkthrough guides later.