Once again an update to the firefox beta program has the potential to break Natwest/RBS online banking. For some inexplicable reason they detect what browser you are using and then make the decision for you whether it’s going to work or not regardless of if the browser you are using will work.
Fortunately, as I’ve previously posted HERE there is a way to solve the problem and fool natwest into thinking you are using a compatible browser.
The new problem is that mozilla have just reclassified the beta release from firefox 3.1 to firefox 3.5. The previous fix involved deleting the beta string from the user agent in about:config leaving Firefox/3.1 or Firefox/3.5 as the user agent. The new problem is that natwest don’t acknowledge the existence of firefox 3.5.
So for the meantime follow the steps in my previous fix making sure the identifier is Firefox/3.1 as before. Least until Natwest catch up or even better remove the stupid browser detection routine