Member system missing one or more frame connections.
Every member system has a start and end frame connection. The lifetimes of these frame connections are controlled by the member system; hence, you cannot eliminate an end frame connection unless you delete the member system. Therefore, a member system without a frame connection should not occur.
Before Version 5 of the software, member systems without frame connections were allowed. Therefore, a migrated model can result in these messages. For a non-migrated model, this situation is abnormal and should not occur.
Commands that select a frame connection are affected. Examples of these commands include placement of members at the end of a member, assembly connection placement on a member system, and placement of analysis boundary conditions.
What You Should Do
To re-establish the connectivity of a frame connection, you can complete a manual process, or run a custom database command.
Before fixing this problem, you must have write access to the permission group of the member system. Frame connections always exist beneath the permission group of the member system. A new frame connection can only be generated if you have access to the member.
Select the member system.
Click the Start and End frame connection buttons on the ribbon. The software creates new frame connections.
Run the Clean Database custom command.
Select the member system(s) in error, and click Clean Now. The software creates new unsupported frame connections.