Thanks for the quick reply!
I cant see what version of WP it was, but I updated probably about 9 months ago, and I needed to update again today when I logged in.
Unfortunately I’m hosting with Yahoo Small Biz, and I dont know thst I can access my WordPress files from there. But I’m in the process of moving everything over to new hosting (for that exact reason), so maybe I should just wait until that goes through, and then I’ll follow your instructions for restoring the old theme (and then update my WP).
Is there a specific process for updating to a new theme that you can point us to, where we might avoid the same blank screen problem when trying again?
FWIW, the one I updated to was Codium Extend:
https://www.ads-software.com/extend/themes/codium-extend
Thanks again!