Have Nortel system. When call comes into line three, it won't recognize any buttons pushed to go to extension. All other lines work fine

SOURCE: dedicated fax line on system phone

If you have a dedicated fax line, the fax should be connected directly to the phone line. If you have the fax line connected to one of your station ports, you may be able to see which LED lights up on your phone when the fax goes off hook. Or you can just try intercomming all extensions in order until the fax rings.

SOURCE: Nortel 1140E IP Phone, Expansion Module 1100 series not working

If you're running on a hosted PBX, the expansion module will not work. It only works on premis based systems.

SOURCE: Nortel M7310 Phone moved to another jack, now no incoming calls

The reason your phones config is not the same as before is because configuration goes by what extension it is. So if you plug your phone in somewhere else, unless you have DN's configured, your extension changes, so say it was extension 21, but now that you moved it, its now 23, those settings remain on extention 21, so if you bought another phone and plugged it into were extention 21 is, it would have the settings that your old phone had before

To access the intercom by just picking up the handset, Press Feature **CONFIG (266344), Select <A. Configuration>, then go to <2. Line Access>, Select that and enter the extension of the phone you want to have access intercom by just picking up the handset. Scroll until you see <Intercom Keys: #,> make sure you have at least one intercom key. Then scroll until you see <Prime Line: #>, Press change until the display reads <Prime Line:I/C>  And there you go. Hope i didn't confuse you 

SOURCE: how do I program the line redirection feature

If you switched phone companies and the feature stopped working you probably had Call Forward Busy/No Answer from AT&T. If you use the call forwarding in the phone it will use two phone lines for the entire length of the call. Call Comcast and have them add Call Forward Busy/No Answer and tell them the number you would like your calls forwarded to and the ring cycle (the number of rings on no answer).

SOURCE: RCA 25414 message light... doesn't

Fix for message light blinking on ECA 25414. Many folks have changed phones or bought used phones to find the message light blinking on the phone especially on lines they don't have. That is what I found on used phones. Leave yourself a message on any phone. Now plug that line into the correct jack in the back for the line that is blinking in other words line 1 or 2 or 3 or 4.. Call the number from the line you plugged in and retieve and delete that message. Hang up and shortly the message light on the phone should go out.