Validation customized cell("B9")

[Maurizio]

Hi all,
I need a formula to Validation "B9" cell:

i.e.
if into B8 there is number "1" or "2" then into B9 I can not put anything

but

if B8 is 3 or 4 or 5 or 6 then into B9 I can put in only 1 or 2


Tia. Maurizio

 

[Eric W]

Try:

=OR(AND(B8=1,B9=2),AND(B8=2,B9=3))

 

[Maurizio]

Try:

=OR(AND(B8=1,B9=2),AND(B8=2,B9=3))

As always many thanks.