1. press ALT+F11 to go VBA window
2. in Project-VBA Project window double click on the name of your
worksheet
3. go slightly to the right where you should see (General) inscription
and click on it
4. you should be able to select "Worksheet" and so do it
5. copy/paste the following code there
Private Sub Worksheet_Activate()
start:
If Len([a1]) = 0 And Now() > [Sheet2!a1] Then ins = InputBox("Before
going to other cells in this worksheet insert value into cell A1 or
otherwise you will not be able to continue", "Insert value")
[a1] = ins
[Sheet2!a1]=Now()
If Len([a1]) = 0 Then GoTo start
End Sub
the macro does the following:
1. checks whether A1 in Sheet1 is empty
2. if so it checks cell A1 in Sheet2 where time and date of last
change to cell A1 in Sheet1 was made
3. if present time/date > than time/date of last change macro shows an
Inputbox where the user is required to insert data
4. if the user does not insert the data before pressing OK and cell A1
in Sheet1 is still empty then Inputbox shows again (until sth. is
inserted)
it would be the best if Sheet2 was made xlVeryHidden so that the user
cannot reveal time/date of last change
if you wish I may send you a file with this macro. write me to
(e-mail address removed)