type in the address bar about:config

then press the button i'l be careful i promise

then type in the bar browser.cache.disk.enable

then double click on it, to make it false

exit firefox and restart-it.

do the same with browser.cache.memory.enable

if you want to read more:

http://kb.mozillazine.org/Browser.cache.disk.enable

http://kb.mozillazine.org/Browser.cache.memory.enable

thank you

Please mark "Solved" the answer that really solve the problem, to help others with a similar problem.

Awesome! Thank you ideato

Well, the solution turned out to be only temporary. Today is Friday, I opened the browser, went to http://www.reuters.com/news/world and what I see are the news from Wednesday. I refresh (F5) get the same thing. Only when I pick World Home from the Reuters menu it shows the updated page.

So: if the caching is disabled for both memory and disk (I just verified these settings with about:config and they are both false) where is the old content coming from? Could my company proxy have it's own caching mechanism? Not likely, if I use IE the fresh content is displayed. I'm lost...

No need to disable the disk cache and the memory cache as that will have performance issues.

You can set the pref browser.cache.check_doc_frequency to 1 on the about:config page.
See:

• http://kb.mozillazine.org/browser.cache.check_doc_frequency
• http://kb.mozillazine.org/about:config

That won't work if you use session restore to reopen tabs on a next start.
In that case you need to clear the browser cache when you close Firefox.

• Tools > Options > Privacy: History: [X] Clear history when Firefox closes > Settings

• https://support.mozilla.com/kb/Clear+Recent+History