I also found the this article which had a lot of useful licence information Where Is Your CRM 4.0 License Key? Or if you go to Settings/Administration/Users/Add Multiple. You can look in the deployment manager in the license tab In the above cases, subscribers can no longer use any software provided through the Visual Studio subscription after it expires.How to find how many licences you have in CRM  Visual Studio subscriptions offered through the Microsoft Partner Network to competency partners and to Microsoft Action Pack partners.  Visual Studio subscriptions purchased through Enterprise Agreement Subscription, Open Value Subscription, Campus Agreement, or other “subscription” Volume Licensing programs Generally, Visual Studio subscriptions that do not provide perpetual use rights include:

If a Visual Studio subscription is transferred or sold, any perpetual use rights are transferred to the new party and the seller can no longer use the software. Product keys that were acquired while the subscription was active can continue being used until all activations for those keys have been exhausted. However, subscribers are not entitled to updates for that software after the subscription has expired, nor do they continue to have access to software or product keys through Subscriber Downloads or to other subscription services that are a benefit of having an active subscription. Visual Studio subscriptions purchased through certain channels provide perpetual use rights that allow subscribers to continue using certain software products obtained through an active subscription after the subscription has expired. Most channels do not allow you to continue using the software after expiration of MSDN: The answer is that it depends on the channel through which you purchased your MSDN subscription.

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