Toshiba M200 - Portege - Pentium M 1.5 GHz User Manual page 111

If the battery does not slide into the slot easily, move the battery
release lock to the unlocked position and try again. Do not force the
battery into position.
(Sample Illustration) Inserting the battery
3 Slide the battery release lock to the locked position.
(Sample Illustration) Locking the battery release lock
4 Turn the computer right side up.
5 Reconnect any cables that were removed in step 3 of
"Removing the battery from the computer" on page
6 Restart the computer.
Mobile Computing
Changing the main battery
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