You haven't provided enough information on *how* you are trying to implement
this functionality. For example, is the UserForm (I presume you meant
UserForm when you said "form") already showing when you are trying to do
this? If so, what event are you using to "kick" your code off (that is, are
you pushing a "Get Active Cell" button to implement your functionality, or
clicking inside the TextBox, or clicking the UserForm, etc.)? If the
UserForm is not already showing, are you doing something on the worksheet
that shows the UserForm and, when shown, you want the TextBox to pick up the
contents of the active cell when loading? I can tell you that the Change
event for the TextBox is probably the wrong place to try and implement your
code (that event will not take place until something changes the text within
the TextBox itself). Provide some more detail on how you want to implement
the functionality you seek and someone here will be able to give you code to
do it.

Rick