Problems in starting Virtual Machines after making my PC dual bootable

I have a laptop, its model is: HP Pavilion Power Laptop 15-cb0xx (12GB RAM, 4 cores, 8 processors).

It has windows 10 Pro as an operating system.

I have installed virtual box on it, then I have created 3 virtual machines:

1- windows 7

2- windows server 2016

3- kali linux

They (the 3 VM) were working correctly, until I make my hp laptop dual bootable, with kali Linux as the second OS.

When I boot on windows 10, I tried to open each VM, but each one gives me an error:

windows 7 stucks at "windows is loading files".

windows server opens windows boot manager and says that windows failed to start with 0xc000035a as a status.

kali Linux shows me an error before booting :

VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED).


Result Code: 
E_FAIL (0x80004005)
Component: 
ConsoleWrap
Interface: 
IConsole {872da645-4a9b-1727-bee2-5585105b9eed}

What happened and what should I do?

(Edit: after marking the VT-x/AMD-V checkbox in kali Linux VM settings, kali now does not show me the same error, but it stucks at a black screen).

I solved it, by removing each virtual machine, and keeping the .vmdk file, then creating 3 virtual machines then implementing the correspondent .vmdk file.