If your Go Direct sensor works on Windows 10 via USB, but you are having issues connecting via Bluetooth wireless technology, the first thing you should check is your Windows 10 version. To check your Windows 10 version:
– Click Start
– Settings (the gear icon)
– System
– About

These steps will generate a list of information about your computer, and there may be a “Version” field. If you don’t see a “Version” field but do see a “Build” field that indicates “10240”, then you are on the first release of Windows 10, (also known at version 1507).

The different versions have different Bluetooth wireless technology configurations, and as such, Graphical Analysis will behave differently on each:

VERSIONS 1507, 1511
These early versions cannot connect to Graphical Analysis 4 via Bluetooth wireless technology. Run Windows Update to get a newer version. These versions are no longer supported by Microsoft and should not be in use.

VERSION 1607
This version is flaky and isn’t recommended. It was released in 2016 and can connect to Graphical Analysis 4 via Bluetooth wireless technology, but you have to pair the device with the computer in Windows Settings before you can connect it in Graphical Analysis. This version is no longer supported by Microsoft and should not be in use.

VERSION 1703 and higher
These later versions can connect to Graphical Analysis 4 via Bluetooth wireless technology, and you do not have to pair the device before you use it. If you do pair in Windows Settings, Graphical Analysis will be unable to connect to the sensor. Version 1703 is no longer supported by Microsoft as of October 2019.

Pairing when you shouldn’t will cause less then obvious error messages:
Graphical Analysis App for Windows reports "The Bluetooth connection has been lost" when trying to connect to a sensor.
The ability to pair doesn’t mean that your computer supports Bluetooth version 4:
How do I know if my Windows PC will support Bluetooth Go Direct?