1. You will need to have access to the CD you created when you first encrypted your hard drive. Insert the CD into the CD-ROM slot and boot off of the CD.
2. Normally when you are booting you will see the Enter password screen, but if you booted from the CD, you will Repair Options menu. Press F8 to go to the Repair screen.
4. Follow the on screen instruction to decrypt the drive. First you will need to enter the valid truecrypt password you used to create a truecrypt hard drive. Then press y when asked if you want to continue with the decrypt process.