Guest Windows XP x86 Does Not Shutdown with Serial Ports Enabled

[yordan]

Host is Windows 10 x64. Serial ports COM 1-4 are from PCI-E Moxa CP-144EL Series card running the version 3.00 driver. All COM ports are working properly on host OS.

Guest OS Windows XP x86 recognizes COM ports 1-4 through the Host Device port mode. Port path on VirtualBox is set to the identical port on host PC. Communication with a connected device is successful.

Upon shutdown of guest OS the shutdown process hangs with:

00:05:15.665094 HostSerial#0: The underlying host device run into a fatal error condition VINF_SUCCESS, any data transfer is disabled
00:05:15.665170 HostSerial#1: The underlying host device run into a fatal error condition VINF_SUCCESS, any data transfer is disabled
00:05:15.665256 HostSerial#2: The underlying host device run into a fatal error condition VINF_SUCCESS, any data transfer is disabled
00:05:15.665307 HostSerial#3: The underlying host device run into a fatal error condition VINF_SUCCESS, any data transfer is disabled

Host has to be rebooted afterwards or rarely BSOD error happens upon shutdown.

[yordan]

vBox log

[SHA]

Log File

[SHA]

Same happens for me on Windows 10 x64 and Guest Windows 7 x64. VBox Version is 6.1.26. Everything else in terms of the moxa card is exactly the same setup.

Can we expect a solution in the near future?