--To retain these as numbers; select the range and from menu
FormatCellsCustom and type as below

00"_"00"_"00"_"00

--OR as text; you can use a formula in ColB to convert
=LEFT(A1,2)&"_" & MID(A1,3,2)&"_"&MID(A1,5,2)&"_"&RIGHT(A1,2)

If you are trying to import this to elsewhere using code you can try the
format function as below

Format(range("A1"),"00_00_00_00")

--
Jacob (MVP - Excel)


"Manos" wrote:

Dear All

I have a fixed coding with 8 digits. (ie: 40000000).
I need to change this and split it importing underscore every two digits in
order to look like (ie.: 40_00_00_00)
Any clever way to do it for 25000 rows?

Thanks in advance for your time.... :)