Hello, I installed wordpress on a site and had to change ownership of the web folder to www-data. Everything worked except now I cannot access the interface I get "Internal Server Error". Where would I see the errors that could be causing this? Also, would ownership changes cause this? Thanks!
That's not necessary and should never be made. If you get an error in WordPress site that wp can't write to the web dir, then you either used a wrong PHP mode (PHP mode has to be php-fpm or php-fcgi) or you missed to enable the suexec checkbox in the website settings. My guess is that you accidently changed the /var/www folder to www-data (and not the web folder of the site, which would be worse enough but easier to repair), which completely messes up the server and it's permissions.
I think you may be right. I took a server image a few days ago. Should I roll back the server rather than trying to repair the permissions?
As a matter of interest for those who may do this an not have a backup from which to restore...what would be the procedure for reversing this?
Restore the correct permissions manually, which is certainly a mess if you have many hosts, but then you probably won't break them or at least you have a recent backup...
