Manual Access to CD-ROM question

How do I prevent all manual access to my CD/DVD drive after my computer locks up with the screensaver? The goal is to prevent anyone with manual access to my comp from removing or replacing any of my CD’s in my drive after I leave. I’ve already tried CDEject but it says that it can’t find my drive. It also doesn’t have an option for me to show it where my drive is. Silly freeware programs.

Windows XP
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