Hi Stuart

>>>I try to get Bios SerialNumber with thi code:
>>
>>It does not work at all on W98 machines.
>
>Could be the issue in http://support.microsoft.com/kb/260710 as I believe Windows 98 does support the WIN32_BIOS class (assuming WMI is installed)
>
>I don't think all BIOSes return a serial number, though.

That is sad, what always returns a serial no.?

Network card need to be present to get it's ID. HDD has both a soft and a hard sr. no., all the ref. I have seen is for soft nos., CPU has sr. no. but can be disabled from the BIOS.

Please advise.

Thanks for your response and link.