Hopefully simple debian host/windows networking issue

[virtualboxRon]

Hi,
I have a debian computer running windows 7 ultimate in virtualbox, and an old laptop on which I have windows server 2012. I connect these two machines with a network crossover cable. This is likely irrelevant but I connect the debian machine to the internet via a usb sim/dongle.

The debian machine is only powerful enough to run one virtual machine. The laptop is only powerful enough to run windows server 2012.

I want the virtualbox>windows 7 ultimate instance to join a domain I have set up on the laptop running server 2012 via the ethernet cable.

I currently have ticked the 'Enable Network Adapter' box under 'Network' in the windows 7 virtual machine settings in virtualbox.
I have selected 'Bridged Adapter' next to 'Attached to'.
The only option available to me next to 'Name' is eth0 (which is my ethernet port).

I have tried every option in 'Promiscuos mode', although I don't think that is an issue.
The 'cable connected' box is ticked.

I tried turning off any debian dhcp server with:

$ sudo service isc-dhcp-server stop
Failed to stop isc-dhcp-server.service: Unit isc-dhcp-server.service not loaded.

(So I assume the dhcp server in debian is not on/installed).
When I run:
$ dpkg -l | grep -i dhcp
ii dnsmasq-base 2.76-5+b1 amd64 Small caching DNS proxy and DHCP/TFTP server
ii isc-dhcp-client 4.3.5-3 amd64 DHCP client for automatically obtaining an IP address
ii isc-dhcp-common 4.3.5-3 amd64 common manpages relevant to all of the isc-dhcp packages

So I guess some dhcp server installed.

When I run ifconfig in debian I get what I think is a different mac address, than when I run ipconfig in windows 7.

I am following a youtube tutorial and am stuck at the point where when I type ipconfig into the command prompt in my windows 7 instance, I am not getting the name of my domain I chose in windows server 2012 in the 'Connection-specific DNS Suffix' field, rather it is just blank.

Would love help moving forward with this! Thanks very much!

[virtualboxRon]

Anyone got a clue on this? Is there any way I can make my situation clearer for instance?

It would be helpful just to know that I have virtualbox set up correctly, for instance. I am continuing looking into this today and would greatly appreciate any help.

[mpack]

Anyone got a clue on this? Is there any way I can make my situation clearer for instance?

Bridging only works with host network adapters, because VirtualBox interposed a filter/redirection driver into the stack for that NIC. If the card doesn't have a standard network stack then VirtualBox doesn't know how to bridge to it. You can double check this by looking at the properties for the card. If it shows the VirtualBox NDISx Bridged Networking Driver then make sure this is enabled (caveat: I just described a Windows host - have no idea what this looks like on a Linux host).

So. If your mobile dongle doesn't look like a network card then you can't bridge to it. You have to use NAT instead, perhaps with port forwarding if there was a particular reason why you chose bridged.