Laptop not detecting battery

Can any one suggest possible solution to the problem-- My laptop can not detect the battery. It can only booth when plug to AC power supply. The laptop is HP 6110. If u can service it please call on my No. 08038968483, 08087080700, 08053523414. I stay in Ejigbo Lagos at the moment.

Is it vista or XP? let me know, i may be able to help. Was it dectecting before?

The OS of the laptop is XP