Automatically change list values

[DKerr]

I should explain it more clearly, cell A1 is has a drop down list
validation with values 'Red' and 'Amber'. B1 also has a drop down
validation list, if Red is chosen in A1, I would like the drop down
list in B1 to have list values A to J, if Amber is chosen in A1, I
would like the drop down list in B1 to instead have values of 1 to 20.

 

[dcronje]

Okay try this:

Name your one range "Red" (Insert>Name>Define and select the rang
$F$1:$F$20 and in the name type "Red")

Do the same for the second naming it "Amber"

In B1 Data>Validiation select list and in the source box type th
following formula

=indirect(A1)

This should now do what you want hopefully.

Let me know if this suits your requirements better