Hello there,

I migrated a Sitefinity project from version 12.2.7230 to Sitefinity 15.1.8300 and it seems the AdminApp config is not loading correctly. as I get following error:

Failed to load AdminApp config: SyntaxError: Unexpected end of JSON input

undefined

It seems its trying to get the configuration from following path which is not available and returns 404 page instead:

https://localhost:44304/sf/system/default.getconfigvalues(configkey='htmlsanitizersettings')?$format=application/json;odata.metadata=none&sf_site=71c3aed6-ad0f-483e-9cbf-27761e97b693

FYI: I replaced the AdminApp folder with a brand new website's AdminApp folder, but it didn't help.

Thanks in advance for any urgent suggestions.