| Text | Object is locked. | 
| Explanation | The object to be locked is already locked, for example, because another user is editing the object. | 
| Action | Wait until the object is available again. If the lock is erroneous (e.g. after a system failure), use the Natural system command UNLOCK to unlock the object. | 
| Text | Error in Application Manager. | 
| Explanation | An error has occurred in the Application Manager. | 
| Text | Locking conflict: object is not locked. | 
| Explanation | Either your networking software has an error, or Natural attempted to release an object which it expected to be locked. | 
| Action | Check your environment. |