virtualbox.org

Hello, I upgraded my pc S.O. from Windows 8.1 to Windows 10
By now I cannot see any network interface
What happened? How can I restore the network connection?

Try reinstalling VirtualBox.

Already tryed. Nothing happened..

Is there a way to at least see what caused this?

We all have this problem!
Nobody can help or want to help!

You're right, reinstall Virtualbox doesn't help.
You only can reinstall your past version (which works).

When you access that pulldown menu, VirtualBox gives you a list of all host network adapters (NICs) for which the "VirtualBox Bridged Networking Driver" service is enabled. There are a limited number of reasons for this service not to be available. (1) is that it was never installed (the OP has rejected this scenario), (2) some glitch in the host (e.g. hitting a maximum number of services attached to a NIC), (3) some new issue such as problems with IPv4 vs IPv6 compatibility. I can't comment on the latter since IPv6 isn't used by anything around me and AFAIK the option doesn't exist for XP hosts like mine. Win10 hosts might have a problem.

All you can do, if you insist on being on the bleeding edge, is watch out for what problems and solutions are posted by others. E.g. you will not that we have a "Windows 10 Hosts" topic stickied at the top of this forum.

Test build 104375 (with filename VirtualBox-5.0.51-104375-Win.exe) solved the issue with bridged networking for me. See Ticket #14578 ("Unable to select network adaptor that has TCP/IP disabled.") for details.
I tested this build on Windows 10 host and it works.