My PCI modem will not function even though installation appears to be correct.

If all recommended troubleshooting procedures have been tried and the modem still does not function, it could be an ACPI issue. We suggest you check with your system manufacturer or motherboard manufacturer for any BIOS updates. It is possible that the BIOS does not fully support the Advanced Configuration and Power Interface (ACPI) and needs to be updated. If there are no updates available for your system and/or motherboard, then the modem will not be compatible until you can somehow disable ACPI in the BIOS. The only way to properly disable ACPI is to disable the ACPI option in the BIOS before installing Windows.