This is not possible with retail keys at all. And this is why I'd love to obtain volume MAK keys for windows 7 professional while I still can, if there's any way I can. Windows 8 is being made available to everyone in just a week, and though I've been playing with it for some time now, I'm not so impressed with it that I'd tell my friends to ditch windows 7. Windows 7 is quite solid and stable, but once windows 8 is publicly released next week, it'll no doubt become harder to purchase windows 7 in any form, retail or volume I'd expect.
I do have a tiny bit of experience with volume MAK license keys for windows 7. As a student at my local area college, we do get access to Microsoft's dream spark program, formerly known as MSDNAA, which gives student's and teachers access to a variety of microsoft software. Much of it is retail licenses, but at least in the case of windows 7, each account holder is given access to 1 copy of windows 7 professional who's product key is a MAK product key with 5 activations available on it. Strangely however, the multiple activation key for windows server 2008R2 that I get with dream spark, only allows for just 1 activation! I'm not quite sure why the key doesn't have at least 2 activations on it, but that's how it goes. Back when I had technet back in 2010 the keys I got for server 2008R2 allowed for an incredible 500 activations. Since I have yet to use even one of these, I will probably use my technet key to activate server 2008R2 next semester when I take a server 2008R2 admin class, rather than the key I got from dream spark, since I get just 1 activation on the dream spark key, and my technet key gives me 500, way way more than I'll ever need.
I've never had volume licenses for windows 7 professional other than the 1 from dream spark, because my access to technet was retail and I was not authorized to get volume license products except server products. There is a level of technet subscription that allows for volume license products, but I have no clue how to get that. As I said I'd be interested in purchasing even a single volume license for windows 7 professional so that in case my computer needs re-installation, or a friend needs to re-install windows, I can help them do it, knowing that I have activations available, not needing to wonder if activation will work or not. If anyone knows how I can legally obtain a volume license for windows 7 professional, I would be interested to know. I would want a license for not more than 10 computers. If there's a way I can purchase a technet subscription or MSDN even, that allows for volume license products to be retrieved, that'd work to.