I would leave all 8 of your lines plugged in at the moment.
Unplugging the dead lines - does not remove them form your Pool of lines in the system. The system assumes you have a total of 16 lines connected (Lines 801 thru 816).
Do this at the 20L Operator phone: Press Menu, System Program, Exit, Lines/Trunks, Pools, 70 enter, Entry Mode - and now press the "Inspect" key. You will see a list of line numbers starting at 801. Press exit, and now press 809 delete, 810 delete, 811 delete, etc. thru 816. Then press inspect again to make sure that only lines 801 thru 808 show up.
Now you need to remove the same dead lines from the Operator phone: Press menu, system program, exit, extentions, lines/trunks, type in the operator ext# and press enter, press Entry Mode, press Inspect - to see what lines show up. Press exit and delete all lines after 808.
At the operator phone, you can test Lines 801 thru 808 for dialtone. Just press speaker and press the 3rd button up from the bottom on the left bank of buttons, next press the button above, then the next one above - now shift over a column and press the bottommost button - until you have checked dialtone for all 8 lines.
If you have any "dead" ones - find out if they should be dead or not - by calling your Telco. If they are trully dead - you will have to remove them as noted above.
If three of your lines have a "stutter tone" - indicating they are covered by Telco voicemail (and that they have messages) - that's OK - as long as you get dialtone after the "stutter".
Tom Daugirdas,
President
STCG, Inc.
stcg.com