A Dev post by Tait Watson on the SWTOR Forums reminds us to install the latest Video Driver. Make sure you are installing the latest version of a stable video driver, not a beta one to be sure it will work properly.
Here’s the full post from Tait:
Hi everyone,
If you have upgraded your PC to Windows 10 and encounter issues with The Old Republic that you did not encounter prior to installing Windows 10, please post a description of your issue, as well as your computer’s DXdiag and MSinfo reports. Please scrub any personally identifying information out of either report.
Before posting, please make sure you have also installed the latest Windows 10 driver for your graphics card. (Note: Some older graphics cards may not have a Windows 10 driver immediately available. You can check your card manufacturer’s website for more information.)
Thanks!
Here is my article about my experience with Windows 10
Check out my guide for Installing DirectX 9 for SWTOR (and any other older game):