You cannot upgrade a Windows XP-based computer to Windows Vista when you put the "Documents and Settings" folder on a partition that differs from the system partition

Consider the following scenario. You try to upgrade a Windows XP-based computer to Windows Vista. When you run the Windows Vista Setup program, the upgrade option is disabled in the Install Windows window. Additionally, the Install Windows window displays the following text: The following message is logged in the Setupact.log file:

Date Time, Info MIG Expanding raw path D:\Documents and Settings
Date Time, Info MIG %ProfilesDirectory% (D:\Documents and Settings) is not on drive C
Date Time, Info [0x080755] MIG DoComplianceChecks: CheckUnsupportedConfig not satisfied (- Your Windows configuration cannot be upgraded.)
Date Time, Info MIG pCheckForPendingRunOnce: found 0 values
Date Time, Info MIG pCheckForPendingFileRename: PendingFileRenameOperations not found
Date Time, Info MIG DoExternalComplianceChecks: calling ntdsupg.dll [DsUpgradeCompatibilityCheck]
Date Time, Info MIG DoExternalComplianceChecks: calling fveupg.dll [FveUpgradeComplianceCheck]
Date Time, Info [0x080021] MIG IsCompliantForUpgrade: failed
Date Time, Info [0x080043] MIG Callback_Compliance: Not a compliant system
Date Time, Info [0x08003e] MIG Not a compliant system, upgrade is disabled

This issue occurs because you put the "Documents and Settings" folder on a partition that differs from the system partition.