I have a sheet that requires a date input. The date is used to calculate days in inventory. I need to be able to limit the text in these cells to dates only. How can I check cells for the correct input and throw up a message if it is not a date?
You can do this using data validation. Select Tools|Validation... In the dialog, choose "Date" from the Allow: dropdown list. You can then choose additional criteria (e.g. date must be between two values you specify). You can also input the error message users see when the criteria are not satisfied. Quite versatile.