Excel won't work with numbers longer than 15 digits. You don't say exactly
how you are importing the data, but somewhere in the process you need to
identify the serial numbers as text. Maybe you could format the destination
cell as text or precede the number with an apostrophe ( ' ). The apostrophe
won't display or print, but will make the number a string.

Carlos

"berryware421243" wrote in
message ...
Hello,

We have a web based asset tracking system, and some assets have long
serial
numbers; for instance,
3100600300030147987
or
3101600300100020220

When we import, cut and paste, or open an HTML format page in Excel with
these serial numbers, they all show up as: 3.1016E+18 and the last 6
digits
get rounded up.

How do we show the correct value for these long numbers in excel?

Thanks