The only major problem I've had with Windows 2000 Professional has been the blue screens that Roxio's (formerly Adaptec's) UdfReadr.sys caused. I recently encountered this problem when I inserted a CD-RW disk into my SCSI Hewlett-Packard CD-Writer Plus 9200i. I did some research and discovered that UdfReadr.sys isn't necessary in Win2K Pro. Microsoft provides the Cdudf.sys driver natively in Win2K Pro for reading Universal Disc Format (UDF) CD-RW disks (aka an Adaptec Direct CD).

To uninstall UdfReadr.sys, I started the Control Panel Add/Remove Programs applet and removed Adaptec UDF Reader. Because Cdudf.sys is still installed, UDF CD-RW disks in my IDE CD-ROM drive mount as expected—but my blue screen problem is gone. According to the Microsoft article "Udfs.sys Has a 2.2 Gigabyte Limitation with DVD-R Media" (, Udfs.sys has a 2.2GB limitation with DVD-R media. Finally, I've read that UdfReadr.sys might automatically reinstall if you reinstall Direct CD.