I just get a Siemens optiPoint 400 SIP phone. Three problems occours. 1-i connect it properly to my LAN and give electricity but no dial tone is coming. is everything alright? 2- i can make settings either with keypad or with web gui ( <ip number>:8085 ) But not registered my SIP server. (This server is on my LAN) i gave it an ip address, and enter gateway and mask. Is anything i overlook? 3- Sometimes it is rebooting itself and about it's repating about in 1-2 minutes untill i plug off RJ-45 cable and plug it again. Please write your answers in english, i don't know german. Thank you.