It worked, but now it doesn't

I'm using Virtual Here on Windows .
Client and Server were installed with Bonjour 20/9/2018
Trial licence, as I'm trialling the software

I borrowed the USB using the client overnight, then the next morning released it.
I then renamed the server and USB device in the client [probably irrelevant], and tried to borrow the USB again a few hours later. However, now it won't bind and the server complains the device is in use on the server.
The USB stick is a software license dongle, and I can see that no one is running the software at the moment.

Server Log from when it worked:
2018-09-20 17:19:37 INFO :>>> Starting VirtualHere USB Server v3.7.3 (Built: Sep 16 2018, 13:41:05)<<<
2018-09-20 17:19:37 INFO :Using configuration config.ini
2018-09-20 17:19:37 INFO :Server licensed to=unlicensed max_devices=1
2018-09-20 17:19:37 INFO :Listening on all network interfaces at TCP port 7575 (IPv6 dual-stack)
2018-09-20 17:19:37 INFO :Found Full speed device [064f:2af9] "WIBU-SYSTEMS AG, CodeMeter-Stick" at address 1
2018-09-20 17:20:46 INFO :10.0.0.55 connected as connection 1
2018-09-20 17:32:08 INFO :Installing driver for class HIDClass {745A17A0-74D3-11D0-B6FE-00A0C90F57DA}
2018-09-20 17:32:09 INFO :OK driver installed try again...
2018-09-20 17:32:15 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-20 17:32:21 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-20 17:32:21 ERROR :Error binding device 1 [064f:2af9] to connection 1, BIND_ERROR
2018-09-20 17:32:22 INFO :Device 1 [064f:2af9] BOUND to connection 1
2018-09-20 21:01:35 INFO :Device 1 [064f:2af9] UNBOUND from connection 1
2018-09-21 00:13:06 INFO :Connection 1 remotely disconnected gracefully (rx msg size)
2018-09-21 00:13:11 INFO :Connection 1 successfully removed (reason:timeout)
2018-09-21 09:55:10 INFO :10.0.0.36 connected as connection 3
2018-09-21 10:17:49 INFO :Connection 3 successfully removed (reason:timeout)
2018-09-21 10:53:45 INFO :10.0.0.66 connected as connection 4

Since then, I've not been able to reconnect, and keep getting the following:
2018-09-21 17:10:07 INFO :>>> Starting VirtualHere USB Server v3.7.3 (Built: Sep 16 2018, 13:41:05)<<<
2018-09-21 17:10:07 INFO :Using configuration config.ini
2018-09-21 17:10:07 INFO :Server licensed to=unlicensed max_devices=1
2018-09-21 17:10:07 INFO :Listening on all network interfaces at TCP port 7575 (IPv6 dual-stack)
2018-09-21 17:10:07 INFO :Found Full speed device [064f:2af9] "WIBU-SYSTEMS AG, CodeMeter-Stick" at address 1
2018-09-21 17:10:24 INFO :10.0.0.68 connected as connection 1
2018-09-21 17:10:37 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:10:42 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:10:42 ERROR :Error binding device 1 [064f:2af9] to connection 1, BIND_ERROR
2018-09-21 17:25:04 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:25:09 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:25:09 ERROR :Error binding device 1 [064f:2af9] to connection 1, BIND_ERROR
2018-09-21 17:34:53 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:34:59 ERROR :Cannot capture device because it is currently in use at the server. Please exit the program that is using the device, then try again. (USB\VID_064F&PID_2AF9\000004031847)
2018-09-21 17:34:59 ERROR :Error binding device 1 [064f:2af9] to connection 1, BIND_ERROR
2018-09-21 17:36:55 INFO :Connection 1 remotely disconnected gracefully (rx msg size)

The USB stick's associated licence control centre has it's own log, and is reporting that the USB is being unplugged when the client requests it, and then plugged back in about 1 second later:
2018-09-21 17:39:44: Removable Device has been plugged IN/OUT!
2018-09-21 17:39:44: The list of available CmContainers has been updated!
2018-09-21 17:39:44: The list of available CmContainers has been updated!
2018-09-21 17:39:44: The list of available CmContainers has been updated!
2018-09-21 17:39:44: A CmContainer has been removed (currently found 0)!
2018-09-21 17:39:44: Access from local(IPV6) to SubSystem (Handle 397)
2018-09-21 17:39:44: Handle 397 released
2018-09-21 17:39:45: Removable Device has been plugged IN/OUT!
2018-09-21 17:39:45: The list of available CmContainers has been updated!
2018-09-21 17:39:45: The list of available CmContainers has been updated!
2018-09-21 17:39:45: The list of available CmContainers has been updated!
2018-09-21 17:39:45: Detecting CmContainer with Serial Number xxxxx (HID)
2018-09-21 17:39:45: A new CmContainer is available (currently found 1)!
2018-09-21 17:39:45: Found new entries: 1

What can I do to make the sharing work?