The VM I was trying to run was running perfectly on a Windows 7 machine. I had upgraded to Windows 10 and tried out the same machine (with all the same configs and vagrant boxes), uninstalled and reinstalled virtualbox several times, but it still doesn't work.
Tried making a brand new VM - that didn't work too.
Some people who had similar 'hostonly' errors have suggested to restart the VirtualBox service from terminal, but I don't know the Windows equivalent of that command.
Anybody had this error before? How do I solve this?
A test build is available at https://www.virtualbox.org/download/testcase/VirtualBox-5.0.1-101902-Win.exe . This should fix the host-only interface creation problem by introducing a 5-second timeout when querying the registry key. We would appreciate feedback (i.e. does it fix the host-only interface creation errors or not, is the timeout long enough). https://www.virtualbox.org/download/testcase/VirtualBox-5.0.1-101902-Win.exe
See https://www.virtualbox.org/ticket/14040#trac-change-55
Uninstalling the current VirtualBox and installing the testbuild worked for me