I downloaded the trial version of Avast and deleted my previous Norton app. Now I am missing 2/3 of my personal folders in Outlook. I had over 30 personal folders and now the only ones that remain are A - C. D - Z have all disappeared. Is there any way to locate or retrieve them or is this irreversible?
First, how did you remove Norton? (You should uninstall via Add/Remove programs, then use their uninstall tool and instructions: http://us.norton.com/support/kb/web_view.jsp?wv_type=public_web&docurl=20080710133834EN&ln=en_US)
What version of Outlook? Do you see all of your data files in Control Panel > Mail > Data files?
Avast only loads a plugin in Outlook to scan messages as they come in or go out. It shouldn’t hide folders or delete them in any way.
You could try loading outlook in safe mode to prevent the Avast plugin from running and see if your folders show up (run Outlook.exe /safemode) from the run box.
Or, you could try repairing your PST file if you aren’t on Exchange http://support.microsoft.com/kb/287497
Did you change any server connections on Outlook’s settings?
Which is why I already suggested to use such a tool in my post: