I have aN NEC DX2NA and the message waiting light keeps flashing but there is no message

You might have got cleaner into the unit (always assuming that you used a cleaner rather than a dry tissue). If so, try putting the'phone in a warm place for a time. It's possible that you could dry it out. If that doesn't work then you could be looking at a repair or replacement.

Blinking Light
Two reasons the light on top of your screen might be blinking or on steady.

• You do not have a voicemail key programmed and the voicemail is alerting you of a new message. Simply dial *8 and check your mailbox.

• Message waiting has been activated. To cancel:
  • leave handset hung up
  • press call1 key
  • dial 873
  • press speaker key

Blinking light on top of Display NEC Aspire

Depending on the phone there will be setup to enable the setting of the timeand date, this can be set to sync with the phone system to auto keep track of the time. You can set up other location times as well. Look for an instruction manual on your phone, on the web via google

On the attendant phone:

1. Press the Message key on the Attendant Add-On Console.

2. Press the DSS key on the Attendant Add-On Console that is associated with the station where Message Waiting is to be canceled.

to turn the callback message lamp off,
press the exit button.
press the mw (message waiting) soft key.
press the all soft key

is the nec dsx telephone voicemail light red or green...?
if it's green, it's not the voicemail light, rather, it's the caller id missed call indicator. just look through your missed calls and it will go out... or if you have the admin software, go to class of service, station, and disable the caller-id alert lamp.
free download of admin software at our website http://www.nec-dsx.com

from operators dss hit mw key then the ext you are trying to clear

There is no such thing as a "Call In Progress" light on any NEC phone system. If you are talking about the Message Waiting light you will need to handle the message, or cancel the forwarding or do Feature 99 Feature.

go to the phone where the light is flashing press intercom #409. you may have to do that more than once. Keep doing it until the light goes out.
If the phone system is a DK 8 orDk16 press intercom 409 this will cancel the message waiting light that could have been cativated by a different extension.

do you have VM on this system?