The 10.13: High Sierra Thread

[rmc2000]

I am experiencing a similar problem; you are not alone. For 2 years I have run 2 DisplayLink adaptors each driving a display without major issues while connected to a 27" iMac 5k. The machine is also connected to two external displays driven directly by the iMac. After updating to 10.13, evening running the latest driver, the machine is experiencing similar issues.

If I connect either of the two adaptors I regularly use, the iMac's built-in display and the additional two displays being driven by DisplayPort from the built-in ThunderBolt ports immediately blank. As soon as zero adaptors are connected, the built-in display and Display Port driven displays come back to life, but are at the login screen. If I log in and plug either device back into any USB port, immediate blank screens and back to the login screen once disconnecting the device.

Originally Posted by JimLondon1

I am running 2 x VGA displays via USB-C-to-VGA and HDMI-to-VGA adaptors from a late 2012 Mac Mini on High Sierra. I am trying to run a 3rd VGA display via a DisplayLink USB 3-to-VGA adaptor. The driver was initially blocked by security but I clicked allow. It is recognised in the System Hardware list - screen grab attached. Also attached, a Verbose report using your Support Tool.

The screens are being shared with other computers via an Adder KVM switch but I've tried adding the 3rd monitor/DisplayLink adaptor directly to a stand alone VGA monitor with the same result. All screens are fairly ancient 17in Dell IXODs

Connecting the adapter alone causes no change. Attaching the display to the adaptor causes the other two screens to go dark and the system to be completely unresponsive, after which a forced shutdown is needed. Hence, the report was created with only the adaptor attached.