This use to be caused with an existing install that had bitraider , solution was to delete the bit raider folder and the .version files
if this is a new install , add the swtor folder and launcher.exe etc to the anti virus and firewall exception lists initially
edit: note that officially windows 7 is no longer a supported OS by the game - see minimum requirements https://help.ea.com/en-tr/help/star-wars/star-wars-the-old-republic/swtor-system-requirements/
Unfortunately, none of that worked, but I did solve the issue. Some parts of Internet Explorer 11 and Edge got corrupted, and reinstalling Windows solved the problem.
