"editor.exe Unexpected error: Pure virtual function was called" Came across this error while opening Arbortext Editor 5.4. What the reason could be.

Received editor.exe Unexpected error: Pure virtual function was called message while checking in a specific topic. Also got debug message window: Wrote message to c:\Users\<user>\AppData\Local\temp\editor.dmp.

Could someone let me know the cause for this error.