Resume from saved state won't reconnect network

[poulbak]

Virtualbox: 4.0.6 puel,
Host: Windows 7 pro x64
Guest: Windows 7 home x64, network: Para virtual network card, bridged to Intel 5100 wireless card, Guest additions installed.

My problem: When I resume a guest from a saved state, Windows 7 guest won't reconnect the network. There's a spinning wheel over the the icon, tooltip says: 'Identifying...'
This stays on for 1 to 2 minutes before connecting, often it won't connect at all.
When I start by booting, everything is fine, it connects immidiately.

Workaround is to disable the para virtual network card and enable it again, then it connects immidiately.

I have tried changing the type of network 'private', 'work', 'public' - no effect.

Since finding the workaround (which works every time), this is of course not critical, but still annoying. I previously had a XP guest, also with para virtual driver, didn't see the problem there, only with the Windows 7 guest.

Have others seen this, and if so, is there a a solution that works?

[poulbak]

Am I the only one having seen this problem, or haven't I been clear enough?
This is a guest only problem! The host stays connected, as expected.

Anyone?

[Perryg]

I am afraid that this issues is a rare one. First most people don't use VirtIO for the network adapter in Windows, (I do but not in 64-bit too many driver signing issues for me) plus it must be a pooling issue or some other Windows issue. Have you asked the Windows social network about this?

[poulbak]

Virtio is signed! Very easy to install, just download iso, attach to cd drive and run the installer.
I didn't even install another network driver first, I just installed Windows, then the virtio and it works - great performance.

I just checked again. When I resume, I can see in my router's log that it has actually given an ip address via DHCP (so some kind of connection is made). Still Windows gives up and says: No connection avaiable.

I am wondering, if it's the difference between 'saved state' and 'hibernate' that somehow does this, but I actually have no clue about what specifically this can be.
My theory now is: Just before Windows hibernates, it disconnects networks, Virtualbox doesn't and this confuses Windows when resuming ... but that's just a theory.