When you are running a guest operating system in VirtualBox (innotek’s x86 virtualizer), it will capture your mouse cursor for use within the guest OS. To use your cursor on your host operating system, you need to use the Host Key. VirtualBox uses the Right Ctrl key as the default key. The laptop that I use VirtualBox on has no Right Ctrl key, so another key is needed as the Host Key. If you are in this situation, or would just prefer that the Host Key be something easier for you to use, follow these steps:
1. Open innotek VirtualBox.
2. Click File and select Preferences.
3. In the left pane, select Input.
4. In the right pane, go to the Keyboard section and click the box next to Host Key (the one containing Right Ctrl).
5. Press the key you wish to be the new Host Key (I used Right Alt as my new host key). The new value will appear in the box.
6. Click OK.