domo,
What was the file extension on those particular files and in which folder were they located? You may have tried to delete files being used by Windows.
Norton intends for you to remove all the files in the "Temp" folder, plus other types of .tmp files. In order to do that, you can also use the link below to clean things up.
How To Clean Unwanted Files From The Hard Drive
Hope this helps.
Grif
When I installed Norton Antivirus, the instructions said to go to Start, Find - temp files, Edit and choose Select All and then Select Delete. My computer deleted a few files and then said "df5007" files - access denied and there are about 100 files after that with the same message. Why, when Norton said to delete all temp files? I am using Windows 98.

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