Hello Stefan,

I'm using Microsoft Word 2007 so it automatically saves in *.docx format. There are no error messages and it happens on all charts that extra formats are added to.

However, there is good news!!

The custom formats must only exist for the current use of Word. After revisiting the document I was working on, the only custom format that appeared was the one I ended up choosing (I guess Word deletes unused custom formats when exited). I can't believe that I overlooked checking that when I was working.

Regardless, I thank you for your concern and help.