there are two main possibilities
the number may be just formated at having extra leading zeros
<format<cell<number select general
if the zeros are still there, the cell probably is probably text rather
than numeric.
double click on one of the cells with the leading zeros and hit enter It may
go back to numeric
if so, enter 1 in an empty cell, copy, select all of the cells with the
leading zeros and paste special multiply
if not use a helper column and enter
= value(trim(a1))
copy to the end of your data
copy this new column and paste special value over the existing data
"Vanessa" wrote:

I have downloaded data from another source and the customer numbers are of
different numeric lengths (ex- 345 and 34567). Excel preceeded the numbers
with zeros to make the character length equal to 8. How to I drop the
preceeding zeros?

Thanks!