Dave Thorp's Blog

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

I remember having this problem running the beta versions of firefox 3 and now the same issue is happening with firefox 3.1 (soon to be firefox 3.5).

Basically Natwest (and presumably RBS) online banking has the most atrocious browser detection routine which essentially looks at your browser user agent string and if it doesn’t match the strings it’s been told work with the site it refuses to let you in. Now this is stupid because the vast majority of modern browsers work with Natwest no problems however each time a new (or a beta) version comes out Natwest assume that it wont work with online banking.

So once again it’s time for my little trick to make Natwest think it’s working. This involves the following steps

• In the location bar type “about:config” and press enter
• You’ll then get a warning about dragons. As Peter Jones isn’t that scary just ignore it
• Find the preference “general.useragent.extra.firefox” and delete the b3 bit so it reads “Firefox/3.1″
• Laugh in the face of Natwest’s stupid browser detection system
• Log into internet banking
• Send me all your money (just kidding)