You might find Data Validation something you can use. Select all the cells
(or an entire column) that you want this restriction on and note which is
the active cell (it's the one in the selection that is not shaded in). Click
Data/Validation from Excel's menu; select Custom in the Allow dropdown and
put this formula in in the Formula field...

=AND(LEN(A1)=4,ISNUMBER(--MID(A1,2,3)),NOT(ISNUMBER(LEFT(A1))))

Note - change my A1 references to the address of the active cell I had you
remember above. That will give you the basic validation; you can come back
later and fill in the information on the other tabs.... so OK your way back
to the spreadsheet. Now try an type in a number that does not match your
specification.

Rick


"Raja" wrote in message
...
I want to ristrict the user to enter data in a format with One Letter and
three number.

In Access I can use Input Mask. Is there a simliar kind of feature in
Excel?