In a workbppk I use in one of the pages I have in 1 column where when I go into it this cplumn has changed its Font from BOLD to normal, Size of font moved from 14 to 10. I have approx 12 workbooks containing 12 of these particular pages each and the fault is on all pages in each book just the 1 column. I always correct the page to my desired format but it has reverted back when I reopen it. Thanks for any help.
I wonder if it is corruption. You could create a new workbook and copy and paste formulas en masse from the old into the new. See if the new workbook exhibits the same issue.