I have an issue with macOS Mojave (10.14.4) where a PNA (Windows CE based device) doesn't mount the Mass Storage drive when connected to the MacBook Pro. In fact, different (recently manufactured) devices with the same hardware, don't mount on macOS 10.14 - an issue experienced on several macOS computers.
Until recently there was no problem with connecting the devices with macOS computers and the mounting of Mass Storage drive is successful at random, but very rarely. There were no OS changes on the PNA in the last few years.
The port on the MacBook works without issues and if I insert the other USB device, such as USB Key it mounts and works correctly. A similar but newer hardware PNA device running a similar OS build connects as a MassStorage Drive without a problem. I'm sure I don't have any other issues such as faulty cable and the PNA connects normally with the same cable to Windows 10 computers. The mass storage drive is mounted without a problem to an older MacBook Pro with OS X El Captain 10.11.5 installed.
On the MacBook Pro with macOS 10.14.4 the device is connected to the computer, which I can see in IORegistryExplorer as the image below but the Mass Storage drive of the device is not listed in disk util.
Does anyone have an idea of what can be done to fix this?
EDIT 30.7.2019: New insights: The mass storage drive indeed connects, but only under these strange conditions:
- Disconnect all USB devices from the computer (this includes turning off the Bluetooth since the integrated Bluetooth module actually connects to the USB hub).
- Reboot the machine
- Connect the device
If the device is disconnected and connected the second time, the device is visible in IORegistryExplorer but the mass storage drive is not mounted the second time, as shown here