Repairing Windows XP

Repairing Windows XP (e.g. because disk was moved into new box).

• first make sure the administrator account has a password
• download the latest service pack and current patches to disk, e.g. with the help of a Linux live system
• make a backup copy of %SYSTEM32%\WPA.DBL and WPA.BAK
• boot from Windows CD, preferrably a recent one
• you may have to enter the administrator password
• select install (not "R" for repair console)
• select repair ("R")
• if installation of some files fails with a bogus error message, skip
• if you can not boot any more, try to boot safe mode
• install service pack and pachtes (may replace files that you skipped before)
• restore WPA ("Windows Product Activation") files
• check activation state: oobe/msoobe /a

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