Some 816 phones won't ring on incoming calls

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To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down, enter #20 the screen should say MMC DISABLED
enter in 1 2 3 4 1 # (that enables programming)
enter in #62 the screen should say day ring assn
press the line you wish to program
press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
press # when finished with the line
repeat steps 2 through 5 for the remainder of the lines you wish to change
press # when finished.

To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down, enter #20 the screen should say MMC DISABLED
enter in 1 2 3 4 1 # (that enables programming)
enter in #62 the screen should say day ring assn
press the line you wish to program
press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
press # when finished with the line
repeat steps 2 through 5 for the remainder of the lines you wish to change
press # when finished.

Hi, it sounds to me like your extensions need adding to the group which your main number ring in to, have a look at the following video or visit http://www.abbeytelecom.com

Hi,

Is your extension programmed for Incoming Ringing on Trunk Lines?...
Needs Engineer programming

To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down enter #20 the screen should say MMC DISABLED
1) enter in 1 2 3 4 1 # (that enables programming)
2) enter in #62 the screen should say day ring assn
3) press the line you wish to program
4) press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
5) press # when finished with the line
6) repeat steps 2 through 5 for the remainder of the lines you wish to change
press #when finished.

To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down enter #20 the screen should say MMC DISABLED
1) enter in 1 2 3 4 1 # (that enables programming)
2) enter in #62 the screen should say day ring assn
3) press the line you wish to program
4) press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
5) press # when finished with the line
6) repeat steps 2 through 5 for the remainder of the lines you wish to change
press #when finished. hope that helps

sounds like your having a couple of problems at the same time. the lines only ringing at station 1 is the default setting of the system my guess is that the time and date are also way off if thats the case.
To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down enter #20 the screen should say MMC DISABLED
1) enter in 1 2 3 4 1 # (that enables programming)
2) enter in #62 the screen should say day ring assn
3) press the line you wish to program
4) press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
5) press # when finished with the line
6) repeat steps 2 through 5 for the remainder of the lines you wish to change
press #when finished.

next, the problem with the cordless not working has to do with the port programming, in default it assigns all ports as multiline sets.
To assign a SLT(single line telephone) port to the system while still in program mode dial #38 the screen should say slt dial type and then 16 0's.
0 = keyset 1=slt set
enter in all 16 digits followed by the # i.e.if your cordless is on port 7 it would look like 0000001000000000 #
lastly the phone that can no lnger recieve calls sounds like the do not disturb or DND has been pressed to stop the alarm from ringing. press the mute/dnd button (light should be off). to cancel an alarm press the ALM/SD button twice and then the hold button.
hope that helps out.

To change the ringing on a prostar 816 you first need to be at a display set (doesn't matter what the extension number is).
with the handset down enter #20 the screen should say MMC DISABLED
1) enter in 1 2 3 4 1 # (that enables programming)
2) enter in #62 the screen should say day ring assn
3) press the line you wish to program
4) press the buttons for the extensions that you wish to ring (the ones in the right next to the handset)
5) press # when finished with the line
6) repeat steps 2 through 5 for the remainder of the lines you wish to change
The code for hold recall is #52
enter in your hold recall time in sec. and in a 3 digit format. i.e. 30 seconds = 030 a minute and a half is 090 and so on.
press # when finished

it sounds like the memory battery on the main board is no longer working which means that it'll happen again.

MMC # 62 controlls which phones ring in Day Mode, if you still have a problem repost and I will help you. Thanks