Private Sub Text1_Change()
Text1.Text = Replace(Text1.Text, "a", ""

Text1.Text = Replace(Text1.Text, "b", ""

Text1.Text = Replace(Text1.Text, "c", ""

Text1.Text = Replace(Text1.Text, "d", ""

Text1.Text = Replace(Text1.Text, "e", ""

Text1.Text = Replace(Text1.Text, "f", ""

Text1.Text = Replace(Text1.Text, "g", ""

Text1.Text = Replace(Text1.Text, "h", ""

Text1.Text = Replace(Text1.Text, "i", ""

Text1.Text = Replace(Text1.Text, "j", ""

Text1.Text = Replace(Text1.Text, "k", ""

Text1.Text = Replace(Text1.Text, "l", ""

Text1.Text = Replace(Text1.Text, "m", ""

Text1.Text = Replace(Text1.Text, "n", ""

Text1.Text = Replace(Text1.Text, "o", ""

Text1.Text = Replace(Text1.Text, "p", ""

Text1.Text = Replace(Text1.Text, "q", ""

Text1.Text = Replace(Text1.Text, "r", ""

Text1.Text = Replace(Text1.Text, "s", ""

Text1.Text = Replace(Text1.Text, "t", ""

Text1.Text = Replace(Text1.Text, "u", ""

Text1.Text = Replace(Text1.Text, "v", ""

Text1.Text = Replace(Text1.Text, "w", ""

Text1.Text = Replace(Text1.Text, "x", ""

Text1.Text = Replace(Text1.Text, "y", ""

Text1.Text = Replace(Text1.Text, "z", ""

Text1.Text = Replace(Text1.Text, "A", ""

Text1.Text = Replace(Text1.Text, "B", ""

Text1.Text = Replace(Text1.Text, "C", ""

Text1.Text = Replace(Text1.Text, "D", ""

Text1.Text = Replace(Text1.Text, "E", ""

Text1.Text = Replace(Text1.Text, "F", ""

Text1.Text = Replace(Text1.Text, "G", ""

Text1.Text = Replace(Text1.Text, "H", ""

Text1.Text = Replace(Text1.Text, "I", ""

Text1.Text = Replace(Text1.Text, "J", ""

Text1.Text = Replace(Text1.Text, "K", ""

Text1.Text = Replace(Text1.Text, "L", ""

Text1.Text = Replace(Text1.Text, "M", ""

Text1.Text = Replace(Text1.Text, "N", ""

Text1.Text = Replace(Text1.Text, "O", ""

Text1.Text = Replace(Text1.Text, "P", ""

Text1.Text = Replace(Text1.Text, "Q", ""

Text1.Text = Replace(Text1.Text, "R", ""

Text1.Text = Replace(Text1.Text, "S", ""

Text1.Text = Replace(Text1.Text, "T", ""

Text1.Text = Replace(Text1.Text, "U", ""

Text1.Text = Replace(Text1.Text, "V", ""

Text1.Text = Replace(Text1.Text, "W", ""

Text1.Text = Replace(Text1.Text, "X", ""

Text1.Text = Replace(Text1.Text, "Y", ""

Text1.Text = Replace(Text1.Text, "Z", ""

Text1.SelStart = Len(Text1.Text)
End Sub
You can obviously put it into an array and all that, but this is a really simple way to do it, and one I've used for a long time. I think you could also incorporate a for loop and some ascii values to make it a little less...long.