organization isn’t authorized to upload change sets
Many of you have seen this below error during metadata migration in salesforce by using changsets.
This organization isn’t authorized to upload change sets to other organizations. For authorization, contact the deployment connections administrators on the organizations where you want to upload changes.
This error is because of deployment settings. Seems like you have not created deployment connection between your source org and destination org.
To create deployment connection follow below steps.
login to target environment -> setup -> deploy -> deployment setting -> select source sandbox from the available list of sandboxes – edit -> check allow inbound change sets check box and save.
Now you can upload the change set to the target environment.