When launching ArcGIS Pro, the following error is returned:
Error: The account cannot be used to authorize ArcGIS Pro as it has already been configured to use in offline mode on some other device.
The license of the account has been authorized to work offline.
Return or check in the offline license based on the license type. For more information on returning an offline license based on its license type, refer to ArcGIS Pro: Start ArcGIS Pro with a Concurrent Use license or ArcGIS Pro: Start ArcGIS Pro with a Named User license.
If the Authorize ArcGIS Pro to work offline check box is unavailable, refer to Problem: Unable to return offline ArcGIS Pro licenses back to online .
If the error persists after the license has been returned or checked in, the license has not been acknowledged by the machine. Contact Esri Support Services to reset the license.