Thank you all for your tips and ideas on "Too many different cell formats". I have simplified the model, standardising & reducing the nomber of formats for future use. I rebuilt the corrupted file and put the loss down to experience.
I have a complex Excel work book model which now gives the following error message when a cell format is changed: "Too many different cell formats" I guess the answer to this problem is to simplify formatting in the workbook. The difficult problem is that I saved a version of this...
