I just recently installed Rank Math and have run into same problem. However, none of the workarounds provided above work for me.
I tried removing the other admin account and only have one admin account now – still get the same error. Downloaded and installed the “Temporary Login Without Password”; created new temporary login link that logs me directly into WP Admin dashboard without a password and I still get same error. I also tried disabling RM “Role Manager” thinking that might have something to do with this issue.
The ticket ‘Not installing properly’ is closed to new replies.