I don't think this is possible, but thought I'd ask here.  I have a situation where I would like to look up a value in another worksheet if the the value in a column adjacent to the lookup contains "DMP".  I know how to write that formula, but if the value does not contain DMP, then I don't want the lookup at all, but want people to be able to choose a couple of remaining values from a dropdown.
Can this even be done?  I think I'm going to have to figure out another way to achieve a similar result.
Thanks.