Drop down menus and blank cells

Following from yesterday's exploits I've now come across a similar problem but this time involving drop down menus

I have two columns A and B

A - states the quantity
B - states the type

If 'A' = '-' from the pull down list (representing zero / not applicable) I want column B to show '-' automatically.

If 'A' shows some other option from the pull down list I want to be able to manually select the type from the pull down list for 'B'

Both lists have '-' as a manually selectable option from the pull down list if that helps.

When I say pull down list I'm referring to Data>Validation tool and selection 'List' and specifying a range.

I'm having trouble creating a formula condition for column B as the list seems to restrict the content and prevent formulas?

Hope someone can point me in the right direction again! Thanks

I'm not sure this answers your query entirely, but try this attachement

Hi Gary,

I downloaded your example but don't see what you're trying to acheive with it. I'm using Excel 2000 is it possible it's not working with my version of Excel?