You may see if you examine the ISV licenses installed in your system (under System Administration menu>Setup>Licenses>License codes), you may see that the user count field value shown for the Demand Forecasting ISV license (DemandForecastingFSL) is a massive number in the order of hundreds or even billions.
Firstly - Don't panic. This value is large by design and is correct for your current license. And we do not use that number/value for billing or any other purposes other than as part of how we license and verify the licensing of users in our product.
If you have any other ISV solutions in your system. Their licenses will appear in the same tab. You may see that the user count value for some those show as 0 or a low number. The licensing mechanism in use in D365FO that Microsoft provides for ISV solution builders like ourselves (and those other ISVs who supply your other ISV solutions), to use, this usercount value gives full control the ISV for how they use that user count field value.
Most ISVs do not use it at all - hence why all of the other ISV solutions have 0 as the user count value. The user count field is something Microsoft introduced to their AX2012 product about 2011. It has remained in their products ever since.
Regardless of its non-use by most ISVs, we at Farsight, do make use of it - because we know the number of Demand Forecasting users in any given environment is never the same as the licensed/named D365FO users in the system.
Because even very large customers (with hundreds or even thousands of D365FO users on their Microsoft license) who use our product, generally have only a few dozen or so users actively working with Demand Forecasting specifically (or with any forecasts in general) in D365FO. Which means our licensing mechanism has to be done a little differently than just counting users.
So ensuring that user count value is other than zero allows us to be able to flexibly license the product for far fewer D365FO users than whatever the number that your current number of D365FO users actually are (and hose actual users of D365FO can and will change over time).
We use the user count value as the 32 bit binary number it actually is, and we use those 32 bits in very precise and structured ways. Which as a side effect of doing so, means that user count value can and does have a wildly varying and usually very large values for any particular customer license.
That number is however fixed to the value it has for the licensed user count of Demand Forecasting users in your license. This number is fixed the moment when we generate/issue the license file to you. That value will not change over the lifetime of that Demand Forecasting license we issue you. So whatever that number you see now, it will remain unchanged in value from the time you first installed that license, until you load your next (replacement) license file. At which time the value of the usercount field may change.
This clever use of the user count value that we have implemented here, gives customers like yourself the flexibility to license/purchase only the actual number of licenses required for your Demand Forecasting usage. Thus ensuring you do not need to buy more users of Demand Forecasting than needed.
You can check at any time the number of users you have and are licensed to have in your system, via the Demand Forecasting parameters form. Open that form and then click the "Info" menu button that is present there.
This will pop up a window like this:
This screen is from a Release 10.0 system, regardless of the Demand Forecasting release you have, your screen will be quite similar. We have highlighted the two lines that display the licensed users and current number of Demand Forecasting users information so you can see it.
If you are eagle-eyed, you may also notice that the value shown for the user count in your ISV license screen also shows here as the "License key hash". Thats intentional - as it lets us confirm the user count value from your ISV license has been loaded correctly.
Lastly the license expiry date, also shows in this ISV licenses screen. If the Demand Forecasting license expiry date shows a date in 2099, this is considered by our system to have no expiry.
If the expiry date shown is, however, for a date in the near future, you must ensure that this license is either replaced or the Demand Forecasting functionality use is ended, prior to this license expiry date, as the ISV license will cease working after that date.
This means Demand Forecasting will no longer show on the D365FO modules menu. But if this happens, when a replacement license is installed, then the new license will reactivate the functionality.