Virtualbox enable nested vtx/amd-v greyed out

I seach for 2 days and nothing worked for me.. then i find the solution:

The problem is in Windows 10... u need to disable Hyper-V Manager ...

1) make sure in your BIOS cpu virtualization is enable.

2) open your CMD as administrator

3) in your desktop folder type bcdedit and look for hypervisorlaunchtype in the bottom ... if it is Auto or enable we need to disable it !!!!!!

See this picture

4) type in your cmd bcdedit /set hypervisorlaunchtype off

5) Restart your OS and be happy !!!

i know this is a old question ... but for everyone who have a similar problem i hope it helps !!

Virtualbox hardware virtualization option is to allow the virtualization capabilities provided by the processor(https://www.virtualbox.org/manual/ch10.html). This does not help with nested virtualization. You can run in Docker in Virtualbox as long as there is no hypervisor running inside. That is the case when we run Docker on Linux systems in Virtualbox. With Windows server, they run hyperv as well on top of which they run Windows server where Docker runs. Thats why nested virtualization is needed here. For this case, use something like Vmware player that supports nested virtualization. I use VMware player for cases where nested virtualization is needed. The other option is to use native Windows server that has hyperv.