that you were/are logged on to an admin (rather than a limited user) account on that computer, then download and run the Norton Removal tool http://service1.symantec.com/Support/tsgeninfo.nsf/docid/2005033108162039 and reboot.
If that doesn't do the trick I'm not sure, but you could probably benefit from a manual search of everything Norton or Symantec on the computer and registry, making sure that hidden files are displayed. (folder options)
(Then, after you've tried AVG for a while, if it gives you any problems, try Avast, or Avira.
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Hi, my Norton subscription expired and, rather than renewing it, someone recommended to use AVG, since it's free and got good reviews on PC Mag website. Halfway through installation it told me to uninstall my other antivirus program first. So I uninstalled norton antivirus, norton goback, norton ghost, all the norton or symantec programs, and tried to install AVG again, but got the same message. What's the next step?

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