Two things:

First you have to declare the RngArr() variable as public as below
(outside the module), and remove the related Dim statement:

Public rngArr() As Range

Second you have a syntax error in your macro, if values is to be
written back to column 7, then use this:

Private Sub CommandButton1_Click()
Cells(rngArr(0).Row, 7).Value = Me.TextBox1.Value
Cells(rngArr(1).Row, 7).Value = Me.TextBox2.Value
Cells(rngArr(2).Row, 7).Value = Me.TextBox3.Value
End Sub

Regards,
Per

On 25 Sep., 20:39, "Patrick C. Simonds" wrote:
I seem to be at a lose to be able to get this to write data back to the
worksheet after the the TextBoxes have been edited.

Private Sub CommandButton1_Click()
* *Cells(rngArr(0).Row,(1, 7).Value = TextBox1.Value
* *Cells(rngArr(1).Row,(1, 7).Value = TextBox2.Value
* *Cells(rngArr(2).Row,(1, 7).Value = TextBox3.Value
End Sub