Unable to rename UserForm to removed userform name

Hello dear helpers,

When I try to rename a userform to a name which I have used before, but since Removed, I get the “Path/File access error” error message.  It seems to me to be a bug in Powerpoint, and maybe other Office programs, but I am new to Powerpoint VBA and am open to suggestions.

I am doing this to use one userform as a base for the structure of further userforms.

The only reports of this error happening which I have been able to find on the web are all Excel based and refer to closing the workbook and Excel and restarting Excel.  How do I get around this in Powerpoint (365)?

My test process is:

    --Restart my computer, then open PowerPoint with a new, blank presentation.

    --Open the VBA editor.

    --Insert a userform (‘UserForm1’) into the VBA forms.

    --Save the presentation.

    --Rename ‘UserForm1’ as ‘My_Frm’.

    --Save the presentation.

    --Save userform ‘My_Frm’.

    --Remove ‘My_Frm’

    --Insert a userform (‘UserForm1’).

    --Rename ‘UserForm1’ as ‘My_Frm’  ===> the ‘Path/File access error’.

Thanks in advance, Phil.