This one is very frustrating.

I'm working on an Excel 2003 spreadsheet which is being tested and upgraded to run on Excel 2013. One of the sheets is protected, with seven cells unlocked for data entry, along with a check box, a dropdown combo box, and two command buttons. The option to select locked cells is disabled, while unlocked cells can be selected.

The problem is that, when the check box is checked (or subsequently unchecked), the seven entry cells cannot be edited. They can still be selected, but typing any new value has no effect. Further, when I unprotect the sheet and check the entry cells with Format Cells, their Locked option is still unchecked.

There is no code associated with any of the check box events. The check box links to a locked cell on the same sheet, which in turn is referenced by a named formula (not a named cell containing the formula) that appears in formulas in several other locked cells on the sheet.

When the original spreadsheet is run with Excel 2003, clicking the check box does not "disable" the entry cells. When that same file is run with Excel 2013, checking the box "disables" the cells. The command buttons and combo box are unaffected in either case.

I'm sorry, I can't attach the spreadsheet, it's proprietary information.

Anybody have a suggestion as to the cause (and solution) of this problem?

Addendum: I found that if I reveal the Formula Bar (in the View tab) and select one of the "disabled" entry cells, I can then edit its contents in the Formula Bar. Further, this "enables" all of the entry cells.