Windows 10 virtual machine starts with black screen, forcibly stopping the virtual machine and starting again makes the issue to be gone, but next starting/restarting of virtual machine will stuck again with black screen.
To know how to forcibly Stop virtual machine check the following article.
1) Some 3rd party software installed within Windows 10.
2) Windows 10 fast startup feature enabled.
3) Interruption of Windows 10 updates installation.
- Perform Windows 10 clean boot:
From Windows Start menu, search for msconfig. Select System Configuration from the search results.
Or Win+R > msconfig > OK
On the Services tab of the System Configuration dialog box, tap or click to select the Hide all Microsoft services check box, and then tap or click Disable all.
NOTE: Make sure to leave Parallels services enabled.
On the Startup tab of the System Configuration dialog box, tap or click Open Task Manager.
On the Startup tab in Task Manager, for each startup item, select the item and then click Disable.
Close Task Manager. On the Startup tab of the System Configuration dialog box, tap or click OK, and then restart the computer.
Check the issue by restarting Windows 10 several times, if it will be fixed, to identify which software/service was causing it, re enable every software/service one by one, once issue will appear again, the last software/service you enabled is the causing one.
- Disable Windows 10 fast startup feature under Power configuration.
From Windows Start menu, search for contol. Select Control Panel from the search results.
Or Win+R > control > OK
Within Control Panel access Power Options
Click the link Change what the power button do.
Click on the Change settings that are currently unavailable link if the Turn on fast startup (recommended) option is grayed out.
Uncheck the Turn on fast startup (recommended) option
- Check the status of Windows 10 updates available and already installed, try to uninstall several latest installed updates or the one that were failing to install previously.
For more information about managing Windows updates check the following article.