I noticed a strange behavior with Excel VBA. The project explorer shows some orphaned sheet objects (e.g. "Sheet16") that cannot be deleted and don't belong to valid worksheets. Looking at these orphans, I can see that they contain callback functions from the originating worksheet (e.g."ShowCI"). A new sheet object which relates to the worksheet (e.g. "Sheet161(ShowCI)") is being created by Excel but it hasn't the callback functions which are still in the orphaned object.
I saw proposals in the web to export things into a new workbook to overcome the issue, but this is annoying (especially if to be done on files using lots of complex VBA and user forms 
) and doesn't really prevent from happening again.
I'm rather interested in avoiding such situations and to know from where these corruptions could result.
So what causes them?
Thanx for helpful advice;-)
Regards