>>>>>>It sure looks like it thinks it is plugged in. You could have a bad charger or battery.
>>>>>
>>>>>This laptop is new. After I complained about the previous problems, they sent me a new additional power supply. I'm using the new one now, but I don't think the problem is in it.
>>>>>
>>>>>May be I need to re-start again :( I didn't re-start for a week or more...
>>>>
>>>>Do you have the old power supply? If so, does it do the same thing with it?
>>>
>>>I can put the old power supply back. Basically, sometimes it's not detecting that power supply is on. In this case I change the outlet and last time I changed the power supply to the new one.
>>
>>You aren't by any chance plugged into an outlet that has low voltage for some reason, or into a UPS that has flakey output?
>>
>>If you can plug into a different outlet in a different room and get it to charge, suspect the outlet or UPS. Some cheap UPSs put out a square wave AC that your laptop power supply may not like.
>
>It's UPS and my other computer is plugged in and it's seating right next to my laptop.
>
>I may try to find a different work place or buy another UPS.

There is a difference as to whether a power supply will run on wierd A/C input compared to whether a battery will accept a charge from the same input. Many battery chargers (including ones in UPSs) will not charge unless the A/C power is within fairly strict limits.

You might also check to see if the battery in the UPS is charged - log off your machine (leave it running) and pull the A/C plug from the UPS to the wall. See if the UPS keeps your machine running.