Hi Martix (a friend of Matrix?)
You cannot add an input mask or calender control to an Access input/meesage box. If you create a parameter query that asks the user to enter "Start Date" or similar then you are restricted to a simple grey box with no fancy features.
The solution is to create your open popup form that prompts the user for the query parameters, perhaps using a combo box (so a list of choices are offered) or using a text box (for which you can set an input mask). You can also call upon a calender control, say by double-clicking in the text box, to display a monthly calender from which the date can be selected and then entered direct into your text box.
The text boxes would then replace your parameter prompts in the criteria row of your query, so instead of:
[Enter Start Date]
and
[Enter End Date]
you would have:
Forms!frmMyForm!txtStartDate
and
Forms!frmMyForm!txtEndDate
This can work very well - it is a technique I and many others regularly use.
HTH
Rich Gorvin