Hi!
> It supposedly uses COM3
Most modern modems are "soft" modems and have only enough hardware to
connect to the telephone line. Everything else--including the serial
port assignment, happens in software.
> I had to get a generic driver from the company. Could this have
> anything to do with it?
Yes. Although it isn't common, some hardware makers do enough
customization that drivers from the actual chipset maker no longer
work. Dell has drivers for the PCTel modem in the Latitude C510.
The list of drivers for your system is here:
http://support.dell.com/support/down...&catid=&impid=
or (shortened):
http://lnk.nu/support.dell.com/np1.aspx
The PCTel modem driver is here:
http://support.dell.com/support/down...0&fileid=63627
(shortened)
http://lnk.nu/support.dell.com/np2.aspx
There was also seemingly a Conexant modem available for that system,
so you might want to make sure that you don't have that modem.
William