GPUPDATE

GPUPDATE – Update Group Policy settings. (GPUPDATE.exe)

Syntax
       GPUpdate  [/Force] [/Logoff] [/Boot] [/Sync]
           [/Target:{Computer | User}] [/Wait:value]

Key:
   /Force         Apply all policy settings, not just those that have changed.
   /Logoff        Logoff after the Group Policy settings have been updated.
                  Some group policy client-side extensions are only processed when a
                  user logs on. (Software Install, Folder Redirection.)
   /Boot          Restart after the Group Policy settings are applied.
                  Some group policy client-side extensions are only processed at startup
                  (e.g. computer-targeted Software Install)
   /Sync          Apply the next foreground policy synchronously (in the background).
                  This can be applied to computer boot and/or user logon. (see /Target)
   /Target:       Update only User or only Computer policy settings
                  default = both
   /Wait:          The number of seconds to wait for policy processing.
                  default = 600 (10 minutes)
                  '0'  = do not wait.
                  '-1' = wait indefinitely.
                  If the time limit is exceeded, the command prompt returns,
                  but policy processing continues.

/Logoff and /Boot will have no effect if there are no client-side extensions called that require a logoff/reboot. /Force and /Wait parameters will be ignored if /sync is specified.
GPUPDATE will apply new and changed policies, it will not remove an existing setting where the policy is set to “not configured”
Example
C:\> GPUpdate /Force