Cannot login and white screen of death

Use your web host’s control panel or an FTP client, and rename your /wp-content/plugins/ folder to plugins-bak.

See if you can then log in. If so, it will be a matter of deactivating your plugins, and activating them a couple at a time until you figure out the culprit.

It seems laborious, but it’s not that bad; we’ve all been there!