hp wont charge

[max76]

I have this HP elitebook 840 that has stopped charging. I have tried numerous AC adapters that work fine on other laptops but the chargers won't charge this laptop. The original AC adapter works just fine on other laptops too. 

When I plug in the charger, the led light for charging just blinks white while it is should show an orange led light to indicate it's charging.  What might be the issue? 

[erico]

The power light blinking is supposed to mean the notebook is in a sleep state. 

From my recollection, It can also mean that there is a memory module issue.

If it blinks twice and then repeats endlessly, it is usually a corrupt BIOS issue.

Are you able to get the notebook to boot to Windows, but it will not charge or will it not boot to a Windows login.? 

[DocEricStrange]

The power light and caps lock keep blinking.

I ordered a new battery, start the computer log into windows 10.

But when i plug the AC adapter, Bolt sign blink 8 times then nothing.

I try to update the bios but got the message Plug in the AC adaptor while it was plugued in

SO in resume, when i plug the AC Adaptor Power and Caps lock Blink infinitly.

Not able to start windows without a Battery.

I did a full reset a couple of times. removing the battery and the AC, holding the power button 60sec, etc...
I tried the Windows Sign key + B button, ilt load but have a blank screen
The windows key + V doesnt work.

Is there somthing else i can do?

Thank you