Check user input format

Hello!

I'm trying to find a way to verify that user input is in a specific format (specifically "mm/dd/yyyy"). Here's what I got:

Dim r As Long
Dim temp1 As String

r = MsgBox(prompt:="Are there any new records?", Buttons:=vbYesNo)

If r = vbNo Then
    Do
        temp1 = Application.InputBox(prompt:="Enter date of last change (mm/dd/yyyy):")
    Loop While temp1 = "##/##/####" 'This is where the issue comes in

    With Range("A7:I7")
        .Merge
        .Font.Bold = True
        .Interior.Color = RGB(255, 255, 0)
        .Value = "NO CHANGES SINCE " & temp1
    End With
Else
    Call WAWAFormatter
End If

Any help is greatly appreciated, thanks!