Enter this formula in C1 of Sheet1, and copy down:

=VLOOKUP(A1,Sheet2!$A$1:$B$21000,2,0)

If you have data in Column B OR Column D on Sheet1, down to row 21,000,
after you enter the formula in C1, click back into C1 and you can simply
*double* click the fill handle of C1, and *automatically* have the formula
in C1 copied down Column C, as far as there is data in Columns B or D.
--

HTH,

RD
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Please keep all correspondence within the Group, so all may benefit!
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"Anthony" wrote in message
...
Your profile has an email address are you on it now and i'll email excel
file
easier than trying to explain without the worksheets




"shail" wrote:

Hi Anthony,

Can you give me an example?

Thanks,

Shail


Anthony wrote:
In simple terms

Column A on worksheet 1 contains 100 rows of 16 digit tag identities

Column A on worksheet 2 contains a list of 21000 rows of 16 digit tag
identites from which the 100 on sheet 1 are drawn. Column B on sheet 2
shows
a secondary unique identity for each tag.

For each tag on sheet 1 need to match and display in column C sheet 1
its
secondary ID listed in column B sheet 2