MATCHING THE DATA AND

Hello,
I have Two MSExcel files,
1. DATA CONTAING OF MANY DEPOSITORS.
2. PERMANENT ACCOUNTS NO's ( PAN ) OF THE DEPOSITORS.

Firstly , all the depositors do not have the PAN.
Secondly , in the First File the Names of the Depositors are not in order.
But all the depositors have UNIQUE CODE NO.

I have entered all the UNIQUE CODE NO of the depositors who have the PAN in the Second file.

Now, I want a formula to:

Search the UNIQUE CODE NO from the Second file and return the PAN of that particular UNIQUE CODE in the next column in the First file.
( I cannot add the data in the same file , because the First File data wll be chaging from month to month )

Please help me how can I write the formula

Reg
CHETHAN
MYSORE - KARNATAKA - INDIA