as the laptop boots you should see some sort of "Splash" screen. In most cases it will be a logo screen of some sort. If not it will be what is called a POST (Power On Selft Test). If you see the splash screen you may have to press ESC, Alt-S, F2, Del, F12, or some combination of keys depending on the manufacturer of your laptop to disable or bypas the splash screen and see the POST.
If you do not see a splash screen, Logo screen, the POST will tell you what kind of video driver you have, do a memory test, an usually tell you at the bottom of the screen what key to press to enter the setup or enter the bios. this is what your looking for.
All of this happens quick and has to be done withint 10-15 seconds of turning the laptop on. Once the Windows logo appears its too late, your not going to be able to get into the bios any more. You may know these things already but since you didnt mention them I figured I would just in case.
As for windows security/domain access and such, yes it is possible to lock you out of loggin in locally and regrettably without some hacking tools there really isnt any way to bypass that security if it was done correctly. There are some LINUX utlities my guys use when our customers forget their passwords or lock themselves out of their own machines and such. But if they were purposely removed from being able to access the local machine using the correct policies and the proper domain rights only a reinstall of the OS is going to help you.
As someone else has said, try to put your XP disk in the drive and boot your laptop. Does it boot from the CD? If so, relax your halfway there and we can get you through this. If not, you HAVE to figure out how to get to the BIOS. If this is your personal machine, try calling toshiba tech support or checking out their website to see if there is anything else you can try to get into the bios.
ANyway, once you can boot from CD, boot from your XP cd. Attemp the install but tell it to delete the partition of the hard drive and reinstall the partition. The big reason for this is that it will reformat the drive and make it seem as if there was not previous version of XP on there. This will prevent it from getting the message that there is a newer version. Another option, as someone else has stated, is use a win98 or ME disk and do the same thing. Boot from it and dont install the OS but just use it to reformat the drive.
Let us know if any of this helps.
[edit] From the Toshiba support website.......
How to access the BIOS Settings on your legacy-free Toshiba Portable PC
Note:
These models are considered 'legacy-free', and offer only a Windows-based BIOS setting utility.
Applicable Models: Satellite 5005-S504, 5005-S507, 5005-S508, 5105-S607, 5105-S608, 5105-S501, 5105-S701, 5105-S502, 5105-S702, 5105-S901, 5205-S503, 5205-S703, 5205-S504, 5205-S704, 5205-S505, 5205-S506, 5205-S5151, 5205-S705, 5205-S119
From the Windows Control Panel, launch the Toshiba HWSetup program. HWSetup provides a user-friendly graphical frontend for modifying BIOS settings. Please note that if you change some settings, you may be required to restart your computer. HWSetup comes preinstalled on your Toshiba portable PC, or it can be downloaded as part of the Toshiba Utilities package for your model.
http://www.csd.toshiba.com/cgi-bin/tais/su/su_sc_home.jsp
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