Updates & Downloads

GPSMAP 66 software version 5.00 Beta

as of October 29, 2020

For any issues that you encounter, please send an email to [email protected]. In your email please include the GPSMAP 66 series model you own, software version, and a detailed description of your issue, along with any steps to reproduce. Please note that you may not get a response to the email unless we need more information on the issue you report.
Although this software is believed to be reliable, it has not yet been released for production and should be used at your own risk.

Fixed issue causing some software updates to fail.
Fixed issue that could occur when clearing geocaching live data while navigating to a geocache.

Download and unzip GPSMAP66_xyz.zip.
Place the gupdate.gcd file, found in the file folder System Software, into the \GARMIN folder of the device.
Disconnect from your computer and proceed through the update.
If you would like to revert to the last public release software, drop the gupdate.gcd file found in the SystemSoftware_Backdate_xxx folder, into the \GARMIN folder of the device.
NOTE: If you revert to an older version of software, all of your settings will be reset to defaults and data may be lost.

IBM-compatible PC running Windows 2000 or later operating system and an available USB port.