Are two ways . One uses ftp command , and second query with command snmpset. I will describe second one because is easier to use it with mRemote NG.
Easy way to restart printer is send SNMPT codes via command line , which is available for Windows and Linux.
This command will sent to the printer query which will force printer restart.
snmpset -v 1 -c public PRINTER_IP ".184.108.40.206.220.127.116.11.18.104.22.168." i 4
snmpset is a part of tools available at : http://net-snmp.sourceforge.net/
Many times tested, always worked.