i have laptop acer aspire 4715z. i have problem with bios password and windows corrupt. i cannot format my pc. how can i reset bios? my laptop using phoenix trusted core.
how can i change first boot into cd drive? without go to bios setting.

I would suggest that you take it into a dealer if you do not know the bios password.

Why did you put a bios password in the first place...

One thing you may want to try is to remove the hard drive from the laptop, then try booting it to see what happens. The below process has worked for me. Hope it helpsyou too.

If, during startup, the bios had been set so the CD and/or USB drives would be checked AFTER checking the hard drive (as many laptops are set by default), the laptop may very well continue to search for a different drive to boot from. If you have a bootable disk in the CD tray (or bootable USB flash drive in a USB port), the laptop should try to boot from one of those sources. IF the disk or USB flash drive contains a bios password reset utility, you should be able to reset/clear the bios password without too much problem. Once the password is cleared, you should be able to access the bios as usual.

disaksen