JTECH's Tracker Freedom wireless instruments require their serial number to be logged on the Instrument Registration screen.  This screen can be accessed by clicking the System menu and then choosing Instrument Registration.  

If no instrument is registered for that device type in the software, Tracker will not attempt to communicate with that device.  However, if you have a different serial number than the serial number of your device registered, Tracker will attempt to communicate with the device of the incorrect serial number.  

*Please be sure there are no typos in the serial number.  All serial numbers are in Hexadecimal meaning they are composed of numbers 0-9 and letters A-F. 

If this does not resolve your device connectivity, the problem could reside with your device hardware or with IRIS (TCI for older versions).  To troubleshoot the latter, please visit the following support article.