virtualbox.org

Hello, my Linux Mint 18 host has network settings 192.168.1.120 255.255.255.0 192.168.1.1 on eth0.
Virtualbox 5.1.2 r108956 network settings as follows:
Virtualbox > Machine > Settings > Network > Adapter 1 > Attached to: Bridged Adapter > Name: eth0 > OK.

The Windows 7 guest usually 'just' connects using a DHCP IP. However now, the IP is a weird 169.254.88.220 255.255.0.0 and no Default Gateway?
So I changed to the static IP 192.168.1.121 255.255.255.0 192.168.1.1.

I haven't changed anything, apart from the Virtualbox upgrades offered.

That is an APIPA (Google it) address. A Windows machine will receive an APIPA address if it is set to get an IP automatically but the DHCP server is not found.

Thanks, I tried again today and a weird DHCP IP of 169.254.88.220 255.255.0.0 is on the virtual box guest OS.
I have set the IP to a static 192.168.1.121 255.255.255.0 192.168.1.1, but this still doesn't connect to Internet?

I'll use a slightly paraphrased short description of the network modes, courtesy of scottgus1 (viewtopic.php?f=2&t=76188#p354679):

• NAT and NAT Service are like the network routers you use to separate your house network from the internet. NAT gives each guest its own "router" so to speak, so each guest is separated from the others and the host. NAT service allows more than one guest to attach to the "router" and be in their own private network together. Internet connection IS possible.
• Bridged puts each guest on the host's physical network, and the guests looks to the physical network just like other new PCs on the network. You'll need a home/office router that acts as a DHCP server as well. Traffic between all guests and PCs and the internet IS possible.
• Internal is a private network between the guests connected to it. You can have more than one internal network by giving new names to your new internal networks. You assign the guests to the internal network using the network's name. Internet connection is NOT possible.
• Host-only is an internal network that also includes the host. More than one guest can be attached to one host-only network. Internet connection is NOT possible.

You have selected Bridged. Bridged means that the guest will try to contact a DHCP server (your router). If it can't communicate, it will self-assign an APIPA address (did you ever look it up?). If you set it manually, it's like declaring yourself the emperor of the Principality of Sealand; nobody cares. Since there is no communication between your router and your VM, nothing will be transferred (in terms of communication).

Are you using WiFi for the Bridge? It might not work. Try either with a wired connection to your router, or try NAT.

Okay, I reinstalled and checked Virtualbox 5.1.4.
Vbox has changed the network settings. I used to set the host network to bridged and the guest Windows OS had Internet and could print locally. Now bridge mode stops the guest's Internet and printing. Vbox network is now NAT and the guest has Internet, but can't print locally due to a different IP.

I changed the guest's IP from 10.0.2.2 to 192.168.1.121, but then the guest has no Internet and can't reach the local printer at 192.168.1.160?

You can not change the VBox NAT address on a whim. It needs to be configured in the back end first. Switch to bridged and fix that.

Okay, I change Vbox from NAT to Bridge Mode.
Now the Windows guest machine shows:
169.254.124.195
255.255.0.0
192.168.1.170
8.8.8.8

I then manually changed the Windows IP from DHCP to static.