Does not ring

root your phone and edit call ring delay in build.prop in the root of your phones system storage.

Did you try unplugging power cord for five minutes? often this fix the problem.

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.

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
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

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 button for the fax line
4) press the button for the extensions that you wish to ring (the ones in the right next to the handset)
5) press # when finished with the line

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

hope that helps

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

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.