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Log in to the CCM
Go to DEVICE tab
Under the General tab on the left, scroll down to LICENSE
First thing you should see is System ID
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Provide the FSII Base II system ID , then ordering part # FSII-BASE-II-25BP-LICENSE (which allows you to upgrade the FSII-Base II from a 5 user system to a 25 user system
Once Clear-Com process your order you will receive a licence code that you can enter (see above) .To enable 25 user mode