Host suddenly can't access internet when VirtualBox runs

[bejo]

Hello...

I installed VirtualBox 4.2.4 on Windows XP 32-bit host.

Then I installed 3 guest OS succesfully: Windows XP, Windows 7 Professional and Ubuntu 12.10. All of them 32-bit.

But then I found something weird: the host can't access internet when VirtualBox runs. Even when no virtual machine running. You just run VirtualBox, and then suddenly the host can't access internet anymore.

The host is a laptop. It accesses the internet via the onboard wifi that connects to a wireless router at my house.

To make the host to be able to access internet again, I have to close VirtualBox, turn off the wifi, and then turn on the wifi again.

I have upgraded to VirtualBox 4.2.6 but the problem persists.

I would be glad if someone could assist me in troubleshooting the problem. I am not as techie as most of you in this forum (and my English is not very good )

Thank you very much.

[mpack]

Are you saying that host internet works when VirtualBox is installed but not running? I ask because there are known problems to do with the network filter drivers that VBox installed to aid virtual networking. Occasionally certain hosts have a limit on the number of filter drivers, and installing VBox may cause that limit to be exceeded. However in that case the problem is introduced when you install VirtualBox, it could block host internet whether or not VBox was running. I can't think why enabling/disabling wireless would fix the problem either... unless it somehow changes the order the drivers are loaded in.

[bejo]

Yes exactly, mpack. The host internet works when VirtualBox is installed but not running.

Installing VirtualBox doesn't seem to introduce any unwanted things to my system. Internet access and everything else is fine.

It is running VirtualBox (even without starting any guest OS) that stops the internet access.

If I close VirtualBox, turn the wifi off and on, then the internet access is restored.

But if I just turn the wifi off and on without closing VirtualBox, then the wifi would not connect to the wireless router.

What information should I provide to help you look at this issue further?

[mpack]

Ok, try this (with VBox not running). Go into Control Panel, Networking, select your Wireless NIC (ignore the obvious "VirtualBox Host-Only Network" thing for this test), go to Properties, see the list of service drivers attached to this NIC, and untick the "VirtualBox Bridged Networking Driver". Run the VBox GUI and make sure your VM is set for NAT networking, as bridged will no longer work. Report back the effect.

[bejo]

Thank you for your time, mpack.

I tried what you told me but it had no effect. Still the same symptom.

[mpack]

Well, the only thing left to try is to go into the hosts Device Manager | Network adapters, and disable the VirtualBox Host-Only Ethernet Adapter. If that doesn't work then your problem has nothing to do with VirtualBox, all appearances to the contrary.