Fatal Error Happening on Some Installations After 1.0.49 Update

If you are getting a Fatal error on your website with the following error:

Fatal error: Uncaught RuntimeException: Error saving action: Error saving action: Table 'dbname.prefix_wp8o_actionscheduler_actions' doesn't exist in /…/wp-content/plugins/action-scheduler/classes/migration/ActionScheduler_DBStoreMigrator.php:44

Or something similar including action-scheduler in the error, then please follow the following steps to fix the issue.

1 Before performing any action, we recommend taking a backup of your database.

2 Use our Repair Action Scheduler plugin that can fix this issue automatically on most sites:
https://github.com/rankmath/_repair-action-scheduler

For a multisite, use the following files:
https://github.com/rankmath/_repair-action-scheduler-multisite

On the GitHub page, we linked, click on the green “Code” button and then on “Download ZIP”. Then upload that ZIP file to your site on this admin page: Plugins → Add New → Upload Plugin

Once you activate the plugin, it should do its thing and then deactivate itself automatically. The following messages might show up:

Created table: actionscheduler_actions
Created table: actionscheduler_claims
Created table: actionscheduler_groups
Created table: actionscheduler_logs

The Repair Action Scheduler plugin has been automatically deactivated.

Then you should be able to activate and use Rank Math without any issue.

3 Here’s a video screencast:
https://i.rankmath.com/KStFug

For Advanced Users

Or, you can install this plugin:

A. Head over to the Snippets menu in the left sidebar and click Add New.

B. Give that post any name and copy the below code in the Code field
add_action( 'init', function() { delete_option( 'schema-ActionScheduler_StoreSchema' ); } );

C. Select ‘Only run in administration area’ option and click the Save Changes and Activate button.

D. Open WordPress Dashboard in a new window

E. Then deactivate recently created snippet from here

F. Then activate Rank Math plugin again.

G. Please disable the Code Snippets plugin if you are not going to use it.

Here’s a video screencast:
https://i.rankmath.com/79gPbv

Please clear all the cache, including the server after following the above process.