I have install win 7 on portege m400 , but pen not working! Please help me!

in what way can't you use it? does it turn on ?

Toshiba Portege M400 User Manual Fingerprint Reader Limitations
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Here is a guide toremove windows passwordwith Windows Password Recovery Tool Professional from http://www.windowspasswordsrecovery.com/Step1: Download and install Windows Password Recovery Tool.
Step2: Burn CD/DVD/USB Flash Drive. (Namely it is to burn a Windows password reset disk.)
Step3: Set the target computer boot from CD/DVD or USB.
Step4:Remove the forgotten Windows passwordwith the burned CD/DVD/USB. Then log on to Windows without a password.
Of course, you can also finish Windows password remover if you have a password reset disk in advance. That's also an easy solution.

Source: http://www.windowspasswordsrecovery.com/windows-password-remover.htm

this should be what you need
http://www.csd.toshiba.com/cgi-bin/tais/support/jsp/modelContent.jsp?ct=DL&os=&category=&moid=1362642&rpn=PPM40U&modelFilter=M400-S4031&selCategory=2756709&selFamily=1073768662

You look very much the unlucky owner of a busted battery.

I'm afraid the battery will have to be replaced. Meanwhile, do not use it with the power supply; not only it will do no good, as you already determined, but it might damage the power supply itself.

dear zy_martinez, get in to the Bios setting and look for SATA setting and disable it, now try to install again.

you need the wacom touch screen driver, just go to wacom .com and all i did was download and installed the driver, i run win xp , not tablet version, and after the driver ws installed the table an pen worked 100%,

touch screen pan tablet window xp driver free download

Open your system bios setup. Then under the boot options make sure your cd drive is one of the drives enabled in the boot path. Hope this helps & please remember to rate my answer. Thanks.

This means that the cmos battery on the motherboard is flat and keeps losing time and date and probably the memory settings, this is only a small disc shaped watch type battery CR2032 and can be found on the motherboard, a pc repair shop would be able to do it for you for a small fee.