Excel, Lookup special characters and spaces

Question

I have an excel, spreadsheet that has multiple sheets.

The first sheet is an index of files, I am using the following forumla to look up a value in column A, references against the index sheet, if it matches then it copies the value from column B from the index sheet.

The forumla is:

=IF($A3="", "", (LOOKUP($A3, INDEX!$A$3:$A$26, INEDEX!B$3:B$26)))

It works for data that has no spaces and special characters, anybody have any ideas why it doesn't work and how I can make it work?

Thanks in advance.

Answer 1

Fixed, all data that is in the LOOKUP needs to be sorted by ascending order.