I purchased a theme several years ago from ThemeForest, for my photography portfolio, and I absolutely love it. Unfortunately, the domain it was hosted on expired when I was not able to get it renewed in time, though I still had access to all the files on my server. I was able to copy the site over to a new domain, but now I get a critical error when trying to activate the theme: "There has been a critical error on this website. Learn more about troubleshooting WordPress." This does not happen with any other theme I have tested.

I deleted the theme in WP, and reuploaded the theme zip (since I still have the original) to see if this would fix the issue but it has not. The theme has been removed from ThemeForest and is no longer available for download.

It's been a while since I directly worked with editing theme files for WP, so I'm a bit rusty. Is there possibly some code in the theme that could cause it to cease working on a new install? It definitely worked fine before my original install on the old domain expired, so I'm confused. Otherwise, could it be something on my hosting provider is now incompatible with the theme?

I can definitely switch to a new theme going forward, but I really love this theme and would love to continue using it for a while longer until I am able to find/develop something else that would be comparable or better. Any advice is appreciated.