Refer to this section if your computer has experienced an operating system error commonly referred to as the "Blue Screen of Death" (BSOD) when using Tracker, and you are also using a USB-to-Serial (Serial-to-USB) Adapter from companies such as Belkin, IOGear, Keyspan, or Radio Shack. 

This problem is caused by an error in the implementation of the drivers for the user's USB-to-Serial adapter.

The client may reference the following STOP error codes for further confirmation:

or
DRIVER_IRQL_NOT_LESS_OR_EQUAL

"The Stop 0xD1 message indicates that the system attempted to access pageable memory using a kernel process IRQL that was too high. Drivers that have used improper addresses typically cause this error.

Stop 0xD1 messages can occur after installing faulty drivers or system services. If a driver is listed by name, disable, remove, or roll back that driver to confirm that this resolves the error. If so, contact the manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, DVD playback, and CD mastering tools."
(Source: www.microsoft.com)

Try to uninstall and reinstall the appropriate drivers for the adapter in question, or try using an adapter from a different manufacturer.  JTECH recommends connecting Tracker™ Legacy hardware directly to the computer via serial port as directed in the Tracker user manual.