Sorry about the duplicate post a minute or two back.

OK. This is wierd!!
I cut/pasted the cells with formuale and data validation to another workbook
and copied them back bit by bit.

=IF(A36="","",VLOOKUP(A36,'[Test Equipment
List.xls]Sheet1'!$A$5:$C$30,2,FALSE))

This formula is fine...

=IF(A36="","",VLOOKUP(A36,'[Test Equipment
List.xls]Sheet1'!$A$5:$C$30,3,FALSE))

....but this one isn't

The only difference is the column being returned. The first formula looks
for a match between A36 and column A in the lookup range then returns the
value in column B. The second formula should do exactly the same matching,
but return the value in column C but comes up with "File Not Found".

I must be missing something really stupid, but what?

Ian