you need to delete and recreate the whole Validation object. Is that
true?

I don't think so.

I want to make the user select something from the dropdown sometimes, but
other times he can either select something or enter his own information.

With a list validation a user entry has to match the list all the time.
There is no option to have it turn itself off say during tea time. You
might be able to get the effect you want using the "custom" type of data
validation. For example:

=OR(EXACT(B1,"off"),NOT(ISERROR(MATCH(D1,A1:A3,0)) ))

This custom validation formula for cell D1 should block any entry that
doesn't match the A1:A3 list unless B1 has "off" in it. (I didn't test this
extensively so it may have to be fine-tuned. I think a blank B1 would allow
any entry too so B1 shouldn't be blank).

One thing about the misleading "ignore blank" option. It does not keep
someone from leaving the cell empty or clearing it. It just blocks (when
it's unchecked) a "blank" entry, like pressing F2, Enter with the cell
empty.

--
Jim
"susiew32" wrote in message
...
| It seems that to change the IgnoreBlank property of the Validation object
for
| a cell, you need to delete and recreate the whole Validation object.
|
| Is that true?
|
| I want to make the user select something from the dropdown sometimes, but
| other times he can either select something or enter his own information.
|
| Thanks in advance.