Virtual Box froze and wouldn't respond to cntrl - alt - delete

[Silverthunder]

VirtualBox 6.0.16 r135674
Host: Linux Mint 19.1 Cinnamon 64 bit
-Memory: 8GB total, minus 2.7GB available to Windows VM
Guest: Windows 10, 64 bit, Guest Additions installed
-Memory: 2.7GB

I was in the process of opening and logging into Think or Swim. But, the screen froze on the login dialogue box and the alert saying that my "screen resolution is not the recommended screen resolution." I expect that alert when the virtual machine is not in full screen mode (which it wasn't).

Admittedly, I left the virtual machine (minimized it) to go do some work in the host, which I am guessing puts more "stress" on the virtual box virtual machine.

When I pressed cntrl - alt -delete, nothing happened.

Finally, I sent the ACPI shutdown signal. Now the virtual machine screen is all black. It has been like that for the last 10 minutes.

Here is the log file. However, I saw that there is a .1, .2, and .3 version of this. This is just the base one, but should I include those, too? I do have 3 virtual machines installed, the first one is the one that I am currently having problems with.

[scottgus1]

Before trying to troubleshoot this guest crash, have you killed the guest off and restarted it? Is the guest running again, if you don't try to start Think or Swim?