There is a need to modify the number of days after which inactive clients and non-persistent VDI clients are removed from the Symantec Endpoint Protection Manager (SEPM) console and database.
By default, inactive client records are deleted after 30 days, if inappropriate for an environment this setting can be changed in the Local Site Properties.
Open and login into the SEPM Console,
Select "Admin" on the left pane,
Select "Domains" at the bottom right,
Select the appropriate Domain in the upper left and click on "Edit Domain Properties" under Tasks,
In the window that opened up, on the "General" tab find the checkbox for "Delete clients that have not connected for specified time",
In the box, edit the field to the desired number of days,
lt is also possible to set a value for "Delete non-persistent VDI clients that have not connected for specified time" on the same tab.