I was a bad boy and made a mess of a few things on my website. I attempted to restore the core files and the database and got a bunch of error messages. I traced them to a problem with a cache plugin. I was able to remove the offending plugin and all the changes it had done to core files. I also put a fresh, new copy of WordPress on my server.
My site is now visible to visitors, although some of the plugins are screwed up at the present time. I could fix that, except when I try to login, I get the error message:
You do not have sufficient permissions to access this page.
I spent hours searching that problem and attempting the solutions presented and nothing has worked. Some of the solutions I have tried are:
1. Installing a new default theme and setting it as my site's theme.
2. Disabling all plugins through phpadmin.
3. Checking the user_meta table in the database to ensure I had the proper admin privledges. (I did.)
4. Creating a new admin account through phpadmin and then logging in with that user. (Received same message.)
5. Trying to login with a generic username I use for testing. (Same message -- it appears no one can log into the site.)
6. Checking that the database name and table prefix in wp_config is correct. (They were.)
I am at the end of my experience. I think what I need is an expert to go sniffing around in CPanel to see what's wrong. Either that or advice on some other possible fix I haven't tried.
Thanks in advance.