Red light wont go off headset wont turn on

I fixed this problem by connect it on the charger,hold +and - keys together for 10 seconds,it started to charge and work well.

The unit needs a full charge. Be certain the BT firmware and software with drivers are current. If necessary, contact the manufacturer support technician for additional assistance.

Indicator Lights:
1.Headset Status Headset Indicator Light
2.Powering on Steady blue, then intermittent flashes
(changes to standby mode)
3.Powering off Red appears and goes off
4.Standby Blue intermittent flashes
5.Charging battery Red solid light. Light indicator turns off when
battery is fully charged and headset is off.
6.Low battery Triple red flashes
7.Pairing mode Blue/red alternating flashes
8.Missed call Purple flashes. Press the call control button
to cancel flashing light.
9.Incoming call Triple blue flashes when ringing.
Power on and off:
1.Turn on the headset Press and hold the call control button until the
indicator glows blue. You will hear ascending
tones.
2.Turn off the headset Press and hold the call control button until the
indicator glows red. You will hear descending
tones. When power is off, indicator stays off.
If none of this is helpful then it may be that your battery is dead, if that is the case then you will need to replace the whole headset. The battery's are not replaceable.

Good luck from Headsets Direct!

Please note that your hand receiver has to be off the hook when using the headset.

This is correct, additionally you can use a handset lifter accessory, such as the HL1 or HL10.

Subscribing Headset to Base:

The headset and the base unit are supplied subscribed to each other. However, if you wish to use a replacement headset with the base unit (or if you lose your connection to the base unit), then you must re-subscribe as follows:

1. Return the headset to the charging base.

2. Press and hold both the + and - buttons on the back of the charging base until the red light on the front of the base starts to flash.

3. Let go of both buttons. The red light should continue to flash.

4. Press the mute switch (black wheel on the top of the headset) straight down until a green light appears on the headset, then let go of the wheel, and the light should remain on the headset.

5. Resubscription is finished when the red light on the base is fully illuminated and the green light on the headset disappears.

6. Remove the headset from the charging base lift telephone handset/press headset button if not using a handset lifter. The headset and base should now be connected.

7. If this procedure does not resolve your issue to try a system reset.

The compatibility setting, in almost 100% of the cases, should be set to "1".  You can find it on the side of the base, it's a little turn wheel that will turn if you stick your thumbnail in it and twist.  I have seen one instance on the Cisco IP phones that requires the compatibility setting to be on 5, so try that as well.
If you have a lifter installed, make sure that the short telephone cable that comes out of the back of the headset's base unit is plugged into the handset port of the telephone (where the handset coily cord is normally plugged into).  You would then plug the handset coily cord into the front of the headset base unit.  Make sure you have that configuration, and try again.
Finally you can try a re-set.  To do this you should lift the headset off of the charging base, make sure the green light on the top of the base is off (the headset is off), and then do the following: 1. Hold down the mute button and the call answer button at the same time. (The mute button is the black little wheel on the top of the headset itself.  If you use the tip of your finger to push that straight in, it will mute the headset) 2.  Keep holding both buttons down until the green light below your thumb on the headset flashes for 2 consecutive series. 3.  Let go.  Wait about 20 seconds then try answering.
If this doesn't work, try a re-subscription: 1. Place the headset back on the charging base. 2. The two microphone volume adjust buttons on the back of the BASE unit should be pressed together.  This will start the red light and the yellow light blinking on the front of the base unit. 3. Hold the mute button down while the headset is still on the charging base.  Hold it down until the red light stops blinking. 4. Disconnect the power to the base so that the red light and yellow light turns off. 5. Plug the power back in after about 5 seconds of it being disconnected and make sure the red light on the front of the charging base is now solid and the yellow light is flashing. 6.  Pick up the headset and try again.

NOTE: Before re-subscribing the system make sure the IntelliStand switch (on the right side of the charging base) is in the "_" position and NOT the "=" position.

To Re-Subscribe:

The headset and the base unit are supplied subscribed to each other. However, if you wish to use a replacement headset with the base unit (or if you lose your connection to the base unit), then you must re-subscribe as follows:

1. Return the headset to the charging base.

2. Press and hold both the + and - buttons on the back of the charging base until the red light on the front of the base starts to flash.

3. Let go of both buttons. The red light should continue to flash.

4. Press the mute switch (black wheel on the top of the headset) straight down until a green light appears on the headset, then let go of the wheel, and the light should remain on the headset.

5. Resubscription is finished when the red light on the base is fully illuminated and the green light on the headset disappears.

6. Remove the headset from the charging base lift telephone handset/press headset button if not using a handset lifter. The headset and base should now be connected.

7. If this procedure does not resolve your issue to try a system reset.

You may need to re-subscribe the headset.

NOTE: Before re-subscribing the system make sure the IntelliStand switch (on the right side of the charging base) is in the "_" position and NOT the "=" position.

To Re-Subscribe:

The headset and the base unit are supplied subscribed to each other. However, if you wish to use a replacement headset with the base unit (or if you lose your connection to the base unit), then you must re-subscribe as follows:

1. Return the headset to the charging base.

2. Press and hold both the + and - buttons on the back of the charging base until the red light on the front of the base starts to flash.

3. Let go of both buttons. The red light should continue to flash.

4. Press the mute switch (black wheel on the top of the headset) straight down until a green light appears on the headset, then let go of the wheel, and the light should remain on the headset.

5. Resubscription is finished when the red light on the base is fully illuminated and the green light on the headset disappears.

6. Remove the headset from the charging base lift telephone handset/press headset button if not using a handset lifter. The headset and base should now be connected.

7. If this procedure does not resolve your issue to try a system reset.

Pardon me if you have already tried this but with my em236c I had to hold the Answer/End button for about 15 sec before it flashed red/blue. The manual doesn't say how long to hold it. It took a couple of tries for me. Hope this helps.

Make sure the headpiece is charged. Turn the headpiece off by pressing the little black button on top of the earpiece and holding for about 5 seconds. Turn the earpiece back on again the same way. You should have a slow flashing blue light on the mic boom. The base station will now try to find the earpiece and within about 20 seconds the red light on the base should be steady and blue light on top should be on.
If this doesn't work you may need to manually pair the earpiece to the base by pressing and holding the Listen Volume Adjust + Button and headset Call Control Button on the earpiece until the light on the mic boom flashes red and blue repeatedly. As above, the base station will now try to find the earpiece and within about 20 seconds the red light on the base should be steady and blue light on top should be on.

Try pairing it like this: Put the phone into pairing mode. Begin with the headset turned off. Press and hold down the silver call control button in for 6-10 seconds. The light will flash blue first. Continue to hold the button down then release the button when the indicator light starts flashing red then blue. The units should link up together.