Hi again,
ok, now I think it is clear what you need!

Here is an attached solution (see file).

Short explanation.
I created a data validation for the year (only 2010-2011 allowed).

I created two lists with months in sheet2, and gave them the names "List2010" and "List2011". At the top of sheet2 there is a formula in Cell B1, creating the correct name depending on the selected year. This cell is given the defined name "ValidListName" (otherwise you can't refer to a "valid range" on another worksheet).

At last I entered a data validation for the cell with the selection of month. I choosed "List" and entered "=ValidListName" as reference for valid entries.

I hope this works as you wanted!

Kind regards
Bjorn

Attached Files

year_v3.xls (19.0 KB, 18 views)