Internal Failure Error 0X80040707

Have reseached this Discussion site thoroughly. This error number has been reported by many and for different circumstances. Here is mine: Have two sons, two new iPods. Have one Dell desktop with Windows XP. iPod software loaded fine into first son's account. Rebooted, logged onto to other son's XP account. Inserted disk. InstallShield Wizard had barely started running when Internal Failure Error 0X80040707 appeared, followed by 'iPod for Windows 2005-10-12 Access is Denied' box. Can proceed no further. Please help! Thanks.

Dell Desktop Windows XP

Windows XP