How do I make an execl cell A3 read-only based on A4?

[Jerome]

How do I make an execl cell A3 read-only based on the value of cell A4?

 

[Niek Otten]

Please explain what you try to achieve.
What should happen to cell A3 or if one would try to change cell A3 if what
happens to cell A4?

 

[Chip Pearson]

You can do it with Data Validation on the Data menu. Select A3 and
then open the Validation dialog. There, choose "Custom" from the Allow
list. In the formula box, enter a formula that returns either TRUE or
FALSE, depending on some calculation based on A4. If the formula
returns TRUE (or any non-zero numeric value), the input value will be
allowed in A3. If the formula returns FALSE (or zero), the input value
will not be allowed. For example, if the validation formula in A3 is

=IF($A$4>100,TRUE,FALSE)

input will be accepted only if A4 is greater than 100. (Of course, you
could shorten this formula to =$A$4>100, but I use the IF for
clarity.)

Cordially,
Chip Pearson
Microsoft Most Valuable Professional
Excel Product Group, 1998 - 2009
Pearson Software Consulting, LLC
www.cpearson.com
(email on web site)

 

[KC]

select Cell A3
and goto 'Data' Menu and choose 'Validation'.
under validation Settings/Criteria choose Allow as 'Custom'
and in the formula field below type in
=(A4<>"Locked")

so this will not allow you to enter anything if A3 if A4 contains the text
'Locked'

is this is what you were looking for?

-kc
*click YES if this works