The Concurrent Publishing error is issued in the following situation:
Your eSpace is currently being locked by another operation. Please try again later. User <user> is publishing eSpace <eSpace> (in Personal Area) since <date/time>:
you are trying to Run the eSpace in your Personal Area while a 1-Click Publish is being processed in the server or another developer with your credentials is also updating your Personal Area. Learn more about Concurrent Running.
or you are trying to execute the 1-Click Publish operation while a Run is being processed in the server or another developer is also publishing the eSpace. Learn more about Concurrent Publishing.
Wait a few moments and try the operation again.
Run the Personal Area | 1-Click Publish | About Error Messages