Update Error: Could not validate update handle Recently, anytime an update to Craft core or a plugin is attempted on my site that requires a database migration I get an Internal Server Error: Could not validate update handle. Does anyone know what handle Craft is talking about here? Looking for help debugging this issue. My guess is that somewhere in the midst of updates and rollbacks the database got out of sync with the source code. Just need to track down where this faulty handle is.
Looks like the issue had to do with my production environment being load-balanced. To avoid errors like these on load balanced sites, remember to set the validationKey and appId config keys in your general.php file.