Forms :: Copy Field Text To Clipboard Error

I have a form with two Text box fields "Username" & "Password"

I want to create a copy button next to each field that will copy the contents to the clipboard.

The password field has the code:

Code:
Private Sub Command228_Click()
Me!Password.SetFocus
DoCmd.RunCommand acCmdCopy
End Sub

The username field has the code:

Code:
Private Sub Command229_Click()
Me!Username.SetFocus
DoCmd.RunCommand acCmdCopy
End Sub

The Username copy button for some reason gives me the following error:

Run-time error '438': Object doesn't support this property or method

Why it doesn't like this field?