Hecke, If you have the number for them I'd be first in line to call...
I went to their site and there's no tel number at all only a "send a message' page.

Have sent a support mail to them 2 days ago and still no reply.

Check your spam filters, I emailed them a few times two days ago and each time I got a response within 3 hours by Gianni.

If I may explain why people think its STEAM doing the cock-blocking...

That is because when the error messsage comes up it is from a featureless
Brand androgonious set up wizard... It doesn't say anything on it besides
the errors message saying," activation limit exceeded "

It does not say solid shield anywhere or UBISOFT or have a technical / help button to a website or a support number of any kind what-so-ever...
So don't be so hard on the guys thinking it is STEAM... When it happened to me I also immediately thought it was STEAM... It a natural assumption...

The fact that they do not put any kind of branding on their activation wizard,
in my opinion is intentional... They don't want you to know who they are and
seem to want to make getting in touch as difficult as possible. And they have been successful in this case.

Is is difficult to put your logo on a wizard. No, everyone does it, it is a branding tool and an opportunity to get your logo on every persons pc. Is is hard to put a support number or mail or web address. No, so why don't they do it?

Now everyone thinks this activation screw up is STEAMS fault.
But it is actually UBIs responsibility, they tell solid shield how many activations
the sim should have. BUT try call the UBI support line in the UK 0871 664 1000.
(Found in the Game Manual)
It is not in use... So again, thanks UBI you muppets.

for anyone interested in solving this fast...

I called Ubi America tech support, at least the americans are customer service obsessed.
I spoke to the guys there and he also tried to get in touch with UBI UK and couldn't... So he escalated my support request to the manager and they promised a swift reply... that was last night and still nothing as of 4.30 pm today. If you want to call them yourself the number is +1 919 460 9778.

To their credit they did seem quite concerned about the activation issue for what its worth.

Sombody know if changing joystick make us loose one activation?
Could be a coincidence but after I removed one usb joystick with FFB (not in use anyway in CloD), I was missing a file next morning,(or after reboot)
and could not start CloD, to fix this I reinstalled, and it did activate once more.

I just changed my mobo and have no problems starting the game. No loss of activation at all. Don't know why that should be the case, but I'm happy anyway!

PPanPan