Windows dosn't start 7 or 10

[KHS]

Failed to open a session for the virtual machine Win8 007.

VT-x is not available (VERR_VMX_NO_VMX).

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

[Socratis]

You remember the requirements in the new ticket page? They're actually listed before the ticket form, so I'm not sure how you missed it. I don't see any of them fulfilled, not even a log...

Attach a (full) log file ("Machine" menu/"Show Log" in the main VirtualBox Manager window) straight away to save time for you and for us. The log file contains a lot of useful information about both the host and the guest systems as well as information about what happened during a particular machine run. Please do not cut and paste it.

Now that I don't have the log, I can't tell what your CPU is. I don't know if it supports VT-x or not. But go to your BIOS and enable "Hardware acceleration" or "VT-x" or something similar. Win7 requires the host to have VT-x available.

BTW, it's usually better and faster, if issues like this one (configuration, question) get first addressed in the ​VirtualBox forums. More than 95% of the issues are resolved over there, which keeps the developers focusing on the bug fixes and enhancements, and there is no need for another ticket to keep track of. For example, yours is not a bug and someone from the developers has to deal with it and close it as "Invalid".