Mouse Pointer Stuck Inside VM VirtualBox - Change Host Key

If you using VirtualBox and your mouse pointer is stuck inside the guest's(VM) window. This is by design. When you are using the VM, the keyboard and mouse input go there. If you want to switch this to host, a specific key can be configured, called as "Host Key" (great name)

Default Host Key

Windows: right Ctrl - Press right Ctrl on Windows to unstuck your mouse pointer

macOS: left Cmd

You can also change this key to any other key in VirtualBox settings:

Look into Guest Addition to get rid of this dependency

Unable to open kernel device '\\.\Global\vmx86': The system cannot find the file specified. Did you reboot after installing VMware Workstation

If you got this error, you are already working with VMWare, so no point in replicating the error.
Solution however is simple and effective, just restart the 'VMWare Authorization Service' from the services console and retry.