Nortel IP phones going to server unreachable even when connected

Make it available :). The Tftp ip that is programmed in the phone or passed out by a dhcp server is unavailable or unreachable. Tftp is typically how the phone obtains it's config. Does your phone work? You can access the phones settings by holding down the blue key and restarting the phone. There you can verify your settings or change them.

This happens for few following errors:
It could be the faulty port on the switch/phone
It could be the DHCP settings on your phone.

Add a computer to your network, and install Microsoft Windows Server on that computer, and enable its "DHCP-server" component. Then, this computer will supply IP-addresses for all the other computers connected to your switch.

The switch is _NOT_ a DHCP-server; therefore, you need to add a DHCP-server.

go to menu --> settings --> network configuration --> server menu and scroll down to server address and give the server ip address and save the settings and reboot

for the answer to the query log on to the web site http://nortel.com/

you have to give ip adress in the print server and configure it and one more thing is that ip address shougt be in the lan network

1. Reset the phone by disconnecting and re-connecting power.
2. When the Nortel logo appears, press each of the four soft keys in sequence.
3. If no other configuration changes are required, press OK repeatedly until the “PC
Port? 1-ON 0-0FF” option appears.
4. Press 1 to enable the PC Port or 0 to disable the PC Port.
5. Select OK to confirm the change.
6. Restart the IP Phone.
When the IP Phone is restarted, the firmware sets the PC Port status accordingly

here you are...
This could be the problem with your signaling server , have you checked it ??
I think it is losing connectivity of T-Lan Network.

What are you connecting into the bsr at distant end, lap top or ip phone

Nortel Contivity will work with the your D-Link router, however its functionality depends on the authentication type (AH will not work), NAT compatibilty mode, and disabling keep alives on the server. Contact your Network Administrator to find out how your VPN is configured. Step 1 Verify that you are using the latest version of firmware on your router. Step 2 Login to the Web Management for your router by entering its IP address (192.168.0.1) in your web browser. The default username is admin, and the password is blank. Step 3 Click the Advanced Tab to access the Virtual Server Settings. There is a list of pre-defined Virtual Server Rules towards the bottom of the page. Find the IPSec Rule. Click the pen and paper icon to edit its settings. Enable the rule, enter the IP address of the computer attempting to connect to the VPN in the Private IP field, then Apply the changes. Step 4 Create a new Virtual Server entry. Name the Virtual Server, "NortelVPN". Enter the IP address of the computer attempting to connect to the VPN in the Private IP field. For the Protocol Type, select Both. Enter 9550 for both the Public and Private Ports. Set the Schedule to always, then Apply the settings. Step 5 Access the Tools Page, then click the Misc button. Disable IPSec Pass-through, then click Apply. If the VPN Server is properly configured to work with clients behind NAT routers you should be able to connect to the VPN.