I have just managed to get rid of one nasty virus, and then installed the Service Pack 1 on my Windows 7 pro 32 bit system. The scans are clean and everything is running back to normal now, except this: I cannot access my online banking website. When I try to, the page does not load, and once that happens, no other page, in this or another tab, can load, and firefox will hang at exit (getting the "Firefox is already running..." message when trying to start it) and has to be killed in the task manager. While browsing in firefox then doesn't work anymore (no pages load), any other application using internet will still work (i.e. skype).
This happens only from this computer, using my laptop on the same internet connection (we have a Wi-Fi router and DSL internet in my flat) everything works fine.
This happens with Firefox AND
IE, except that with IE it doesn't hang and I'm still able to load other pages.
I'm running Firefox 4.0.1 and IE 9.0.8112.16421.
The website I'm trying to access is https://banking.postbank.de/app/welcome.do
I've installed the latest Java : (Build 1.6.0_25-b06) but it didn't help solve the problem.