ian
i have come across an alternative that might interest you

Option Explicit
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Trim(Range("B20").Value) < "" And ActiveCell.Address = "$B$21" Then
Range("B20").Select
If Trim(Range("B21").Value) < "" And ActiveCell.Address = "$B$20" Then
Range("B21").Select
End Sub
regards john
"Ian" wrote:

Thanks for the feedback.

--
Ian
--
"john tempest" wrote in message
...
thank you ian that now works great
john

"Ian" wrote:

I think the problem is that you have 2 subs with the same name. If you
put
all the code under the same sub, you should be OK.

If you paste my code immediately after yours, then delete the End Sub at
the
end of your code and the Private Sub line at the beginning of mine, it
should work. As my code protects the sheet after runnign, you may find
you
have to move the Activesheet.Unprotect line to the top of the code to
avoid
any problems.
--
Ian
--
"john tempest" wrote in message
...
thank you ian but i am still having problems. i get the error ambiguous
which
i can understand as i have the following code already in the sheet. how
do
i
get both sets of code to work on the same sheet
thans again john
Private Sub Worksheet_Change(ByVal Target As Range)
Dim WatchRange As Range

Set WatchRange = Range("B4:B7,B25,B16:H16")

If Application.CountA(WatchRange) = WatchRange.Count Then

Sheet111.Visible = xlSheetVisible
Else
Sheet111.Visible = xlSheetVeryHidden
End If
End Sub

"Ian" wrote:

Try this:

Private Sub Worksheet_Change(ByVal Target As Range)
ActiveSheet.Unprotect
If Range("B20").Value < "" Then
Range("B21").Locked = True
Else
Range("B21").Locked = False
End If
If Range("B21").Value < "" Then
Range("B20").Locked = True
Else
Range("B20").Locked = False
End If
ActiveSheet.Protect
End Sub

--
Ian
--
"john tempest" wrote in
message
...
say i have 2 cells B20 and B21. when i enter a number in B20 i want
B21
to
lock, i also want this to work via versa so if i enter a number in
B21
i
want
B20 to lock. this is so a number cannot be put in both cells
is this possible
thankyou john tempest