I bought a new computer recently and I’m moving my files from one localhost to another. When I brought over a website I’ve had no issue with to date, I couldn’t login. I was getting a $_SESSION Variable not set error. So I cleared the cache folder to see if that would help but unfortunately it made it worse. When I cleared the cache I couldn’t see the site at all and was getting an Error 503: Site Temporarily Unavailable. I checked all my config.core.php files and they are correct.
Unless the new environment is precisely the same (same logins, same file structures, same database) you’ll likely need to update core/config/config.inc.php. Alternatively you can try running through the setup which will also help diagnose misconfigurations from the migration.
I copied and pasted the entire folder over, duplicated the database and imported it to the new phpMyAdmin with the same name. I’ll try running through the Setup again to see if I get anything
I found the solution. My WampServer64 has 2 server choices. One is MySQL and the other is MariaDB. I had added my database to the wrong server. It was automatic on my previous computer.