I had the same issue before. Changing the date format in expression columns can be a bit tricky, depending on whether you’re using GridGroupingControl or DataGrid.
Hi french macdonald,
Thank you for reaching out.
If you are using GridGroupingControl, please refer to the following KB article to achieve your requirement: How to change the date time Format in WinForms GridGroupingControl?
Alternatively, if you are using DataGrid control, you can refer to: How to set the custom date time format in WPF GridDataControl?
Revert back for any queries.