If, after a couple of weeks, if you are comfortable with SP1 and if you are sure that you will not need to uninstall SP1, then you may wish to consider removal of several 100 MB of such back up files and reclaim disk space. You will be able to free disk space of 600-800 MB. Vista SP1 integrates a tool named Vsp1clean.exe situated in the system32 folder.
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