On Mon, 16 Jan 2012 22:17:05 -0500, GS wrote:

Uh.., I'm seeing that this approach raises a 'Type Mismatch' error in
the first loop where it loads colB into the collection.

Also, this approach empties colA and raises an error trying to write
the output array because the UBound(vColA) and lBlanks are the same
value.

What am I missing?

If your data is numbers and not text strings, you can see that. Key has to be a string.

It is probably safest to always use Key:=Cstr(x)
That should have no affect on string data, but will convert numeric data to strings.