Virtual box: Black screen after boot (after Guest Additions

I created a new VM for a Win10.1 system to test the new features of the Fall Creator Update. Everything went well, new system updated itself, and finally I installed the Guest Additions too. Right after the installation of it I got this problem. Some Google search showed me this is a common problem (many thread mentioned it on Linux machines as well). The solution usually is turning on or off the 2D and/or the 3D acceleration in the VM settings. I figured out an other way to solve it and worked, at least for me, even after the damage was done. I thought it could be something with the new display driver what the Guest Addition installs. With some hustling (clicking on the red X to close the VM windows brings back a interlaces like screen, so on this snapshots at least I could see what I had on the interface of the Virtual Win. I rolled back the display driver, and voila, it works again. Good luck everyone...

Your browser sent a request that this server could not understand

My browser forgot how to talk to servers? :) After the struggling with the typing issue yesterday, today I got a new one. Some https website doesn't come in. Not all, Google for example works but mxhomepro.com from URC does not. DNS flush, deleting cookies, re-registering some dll... Still nothing. Running Antimallware found some registry issues, quarantine them. Restart... And all good. Still don't know what was that, maybe some commands yesterday, what I run in Terminal and PowerShell? Misery...

Can't type into Cortana and Search in Windows 10

I found that the keyboard did not work for any Windows 10 Modern Apps, just for the traditional desktop apps. 

As a temporary solution you can run ctfmon.exe from Command Prompt (Admin) but it works only till the next reboot.

For a more permanent fix:

1. Open Task Scheduler
2. Go to Microsoft > Windows > TextServicesFramework
3. On MsCtfMonitor, do a right-click and enable the task
4. Restart your machine

That's it. All the search boxes and other entry boxes should work again.

If the task MsCtfMonitor is missing from the list of tasks, you can import it with the .XML file.