The INACTIVE_OWNER_OR_USER error can occur during a data deployment when attempting to assign a record to an inactive user.
What causes the error?
By default, Salesforce does not allow you to assign records to users that are inactive.
If you try and assign a record to an inactive user, it will return a INACTIVE_OWNER_OR_USER error with the IDs of the records which cannot be deployed.
Gearset will show an error like so:
A common example of this is when attempting to restore from a backup when the user that created the record is now set to inactive.
How do I fix the error?
First, consider whether you wish to reactivate the user in question in order to proceed with the deployment.
Alternately, you can change some user permissions to enable you to update records with inactive owners:
Click Setup
In the Quick Find box, enter User interface and select the User interface menu option
Tick the Enable “Set Audit Fields upon Record Creation” and “Update Records with Inactive Owners” User Permissions box as shown
Enable Update Records with Inactive Owners of the user profile or in a Permission Set. More details in this article.
Once you have followed these steps, try rerunning the deployment.