Recovering without a full restore.
THE SYMPTOM
The site was working, you installed or updated something, and now it is not.
THE FASTEST FIX
Rename the extension's directory through File Manager or SSH. This disables it without needing access to the administrator area.
For WordPress, renaming the whole plugins directory disables everything at once. Rename it back and then disable individually to find the culprit.
IF YOU CAN STILL LOG IN
Deactivate the extension normally.
IF IT AFFECTED THE DATABASE
Some extensions modify data on activation. Deactivating does not always reverse it.
Restore the database from before the installation if the data is wrong.
IDENTIFYING WHICH ONE
Disable everything, confirm the site returns, then enable one at a time, testing after each.
Tedious and reliable.
AFTERWARDS
Report the problem to the developer if it is a genuine bug Consider whether you need that extension at all Check for an alternative if it is unmaintained
PREVENTING RECURRENCE
Test on staging, back up first, and install one thing at a time.
