laptop voltage reading high

I have a laptop that won't run off of battery.  Windows says that there's no battery installed, but there is.  The battery is rated for 14.4 V, but when testing the battery when a multimeter it's 16.4 V.  I've only come across low voltage battery's, never a high one.  What could the problem be?  Bad battery?  Bad a/c adapter?  Bad motherboard?

Thanks
MalamamotoAsked:
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nobusCommented:
it is quite possible that the battery - when not charged, shows higher than default
so connect a 15-25 ohm resistor (20 -25 Watt model) across the + and - connector, and measure again
but if the laptop won't run off battery, it can be due to different causes :
1- bad battery
2-good battery - but bad charging circuits of laptop =  bad mobo
3-good battery - but bad AC adaptor (you can measure the output also  - with the same charge for the laptop; ) it measures normally 19 V (specified on the adapter)
4-bad cables, or connectors in the charging, or power circuits

useful info :
http://www.fonerbooks.com/laptop11.htm
 http://techchannel.radioshack.com/test-laptop-battery-1638.html
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MalamamotoAuthor Commented:
Great info!  didn't know a higher voltage could also mean bad battery.  Thanks!
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