my firefox works but my safari will not load anything

Any l message when you try to load Safari?

Mail and App Store working?

I'm having the same issue. Firefox works but Safari doesn't . I dont get any sort of message on Safari. If I try to visit anywhere it just sits. Eventually the "windmill" appears and then Safari completely freezes. I have to force quit it and force quit says that it is "not responding". I don't use the Mail app, but the App store seems to work. This all started after updating to OS-X security update 2015-003.

What OS version are you running?

10.10

Safari/Preferences/Advanced - enable the Develop menu, then go there and Empty Caches. Quit/reopen Safari and test. Then try Safari/History/Show History and delete all history items. Quit/reopen Safari and test. You can also try try Safari/Clear History and Web Site Data. The down side is it clears all cookies.Doing this may cause some sites to no longer recognize your computer as one that has visited the web site.

Earlier.

Safari/Preferences/Advanced - enable the Develop menu, then go there and Empty Caches. Quit/reopen Safari and test. Then try Safari/History/Show History and delete all history items. Quit/reopen Safari and test. You can also try try Safari/Reset Safari. The down side is it clears all cookies.Doing this may cause some sites to no longer recognize your computer as one that has visited the web site.