If you’ve experienced an issue with Safari 5 where it works perfectly some times and other times it doesn’t load a page at all even though you are sure you have a network connection?
If so, do this:
Well sometimes in the folder /Library/Internet Plug-Ins/ are plugins that are older that can cause Safari Problems. Plus if she takes all of the plugins out (to test) she can always reset Safari (or any application) by going to the folder /HerHardDrive/Users/HerUserName/Library/Preferences/ and find the file com.apple.Safari.plist and move it to the Trash can.
sited from this article on macosx.com