Login loop problem: one solution

Had an issue today with the network that my server (with EE 2.7.2 installed) sits on go haywire, and it crashed the server. Had to do a hard reboot. When it came up, I couldn’t login to the control panel, it would just loop right back to the login screen. The frontend of the site was fine.

Poked around for a while to see if anyone had encountered this sort of situation, and couldn’t find anything that would work, so I followed this process:

1) turned on debugging in the admin.php file (switch $debug = 0; to $debug = 1); and uploaded the file

2) went to /admin.php, and saw the error 1062, duplicate entry in ‘exp_security_hashes’

3) I guess this indicated that somehow the entry increment was out of sync with the actual table, so when it tried to assign a new security hash, there was already one there

4) accessed the database via phpMyAdmin

5) backed up the database

6) tried to delete the problematic entry but got another error that suggested repairing the table

7) repaired the table

8) error went away and I was able to login.

9) turned off the debugging

Just thought this might help someone down the road… it ate my lunch today.