I would suggest running the defrag utility or disk clean up since it is only happening on the single users computer, you may just need to do a clean up. You might also want to look at other programs that are running. If you have too many running at the same time this could slow things down. Also, check to see if your RAM can be upgraded. I hope this helps!!!
Norton is quite a memory hog…but it sounds like it is a local problem. As Mom2three suggested, run the disk cleanup utility and then the defrag (if you defrag first, and then go and delete a bunch of files, the defrag isn’t as efficient as it could be). You may want to check for extraneous entries in your registry. Here are some programs that find duplicate files, *.log files, old shortcuts, and useless registry entries:
Hope this helps!
There are many reasons why a file could be slowly to open. However, it is commonly caused by computer viruses infecting the entire system. Basically, not just the file which is slow to open, but the overall response of the system is slow.