Diagnosis
You have expanded a hierarchy tree. It is essential that every new nodebe assigned a unique key (used as an internal ID for the node). Thegeneration of a new key failed.

System Response
The program terminates.

Procedure
Restarting the program may fix the problem. This problem only occurs ifa large number of node keys (>100000) have the same first 12characters. If you have been using the program for a long time sincethe last restart, the supply of available keys may have been used up.
New keys are available after restarting the program.
The likelihood that this error will occur is very low. If you do nothave an enormous number of almost identical entries in the hierarchytree, the error may be due to a program error.