Thanks for the tip! Using that format, the license was accepted.
I received the license in the following format.
----- BEGIN LICENSE ----- Your Name Single User License 0000-0000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ------ END LICENSE ------
It wasn’t obvious why it was in that format or why Sublime Text couldn’t accept it. I tried reformatting to the following, but I still received the same generic error.
----- BEGIN LICENSE -----
Your Name Single User License
0000-0000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
------ END LICENSE ------
Moving “Your Name” and “Single User License” to separate lines did the trick.
It seems like a better user experience to have an informative error message if the entered license is in the wrong format. Even better would be if Sublime Text reformats the license automatically before giving an error.