Virtual Box - unable to save setup due to 'invalid setting'

Hi,
I recently enrolled course and just downloaded Virtual Box and setting up Kali.
I am supposed to update setup by updating Network to NAT Network.
However I am unable to save the update, as it flags ‘invalid setting’ in Setting > Acceleration tab, as shown in screenshot.
Even after I disabled Hardware Virtualization under Setting > Acceleration, the ‘OK’ button still doesn’t appear.
Can anyone help how I can save updated setting ?

Thank you

Are you able to start the VM without changing any settings? Also, try changing that paravirtualization interface to None and uncheck the hardware virtualization and see what happens.

Thank you for your reply.
No, I can’t start VM without updating setup, as Network setup is incomplete.
I already did what you suggested (paravirtualization interface to None and uncheck the hardware virtualization) but OK button is still disabled so I’m stuck basically.

Even tried to enable virtualisation from BIOS but there’s no Advanced tab and can’t find a way to unhide Advanced tab either.

Thank you.

Look at this link to enable virtualization from BIOS or to check whether it is enabled or not. https://2nwiki.2n.cz/pages/viewpage.action?pageId=75202968. Move accordingly based on your model. Also, try installing VMWare Player and see if you can start the VM in that.

Look at this link to enable virtualization from BIOS or to check whether it is enabled or not. https://2nwiki.2n.cz/pages/viewpage.action?pageId=75202968. Move accordingly based on your model. Also, try installing VMWare Player and see if you can start the VM in that.

Hi. Thank you for coming back to me. I am unable to advanced option on BIOS window.
Yes I am using an old laptop.
I will update OS to Windows 10 and see if I am able to enable VT.
Thank you.

Turned out the processor doesn’t support VT-x. I need to find alternative laptop to build a lab.

Oh, I see. I think you are using a really old laptop then. Well, looks like it’s time to buy a new hardware