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When you log in to the Controller, the Console will displays a license expiration informational message if your license will expire within a week, and an error message if your license already has expired.
Additionally, if you have configured the Controller for System Notifications, system notifications are sent when the Controller license will expire in seven days and if the license already has expired.
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Check the System Details widget (view the system-defined Home Dashboard or, on the Reporting navigation pane, click Widgets) to see how many days are left on your license.
The Days: #/# entry in the License field indicates the current day of your current license and the total number of days in the license. If the numbers are identical, your license has expired.
Method 2
Check the Controller log file.
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