Procedures followed (software installed then hardware). W2K locks up on reboot. Removal of card restores boot sequence. On Safe mode boot up and w/ card installed the DWL-520+ resides in Device Manager and states card is working. Other sources suggest: Psbl conflict with sound, disabling PCI Bus Mastering, disabling PCI Serial Generation, disabling unused Com/Lpt ports. These suggestions don't imply much compatibility with W2K. Anyone with a good handle on what the real problem is, and what a solid fix would be.