Did you do a Clean Install?
No, I used the non-destructive re-install in the guide you linked to, but my success at the bank's site was short-lived. The only things I did over the 24 hours after my last post were re-installing my Avast (the Windows re-install caused changes to it that made it not run), running MBAM, Avast, and SuperAntiSpyware scans (nothing found), installing foobar2000 (my preferred audio player), moving my music folder contents (about 10 gigs of mp3s) and Then about 36 hours after I finished the Windows re-install, the same problems started happening at the bank website. One new wrinkle is that in addition to the original error screen I had always seen when the glitch happened before, I'm sometimes now seeing a different error screen with the 404 not found error message.
Another irksome discovery was that due to my stupidity regarding the space allocation for Restore Points, I had wiped out the System Restores I had made previously which might have helped me discover what, if anything, I had done to cause the glitch to return. I've fixed the Restore space allowance, though. Kicked it up to a good 50 gigs just to be safe since I have room to spare.
I got off work a little early today and decided to try and duplicate the initial success I had following that guide, but all I did was waste a good 4 hours. I tried going online to my bank with every iteration of Internet Explorer just like I did last time, but the glitch was there from the very beginning this time. Ugh.
Now I'm wondering what to try next. I don't know if you think I should try a completely clean install or not. I was reading up on all this install/re-install/repair/backup/restore stuff, and I wondered how you felt about possibly wiping the drive clean and using some cloning/imaging utility to just copy the old drive to the new one. I'm just grasping at straws at this point, and as soon as you run out of ideas the only thing I can think to do is try asking for help from someone on the software side of things.
I've been checking my old hard drive (the one that's dying-but-not-dead-yet) once a day at least, and it still has absolutely zero problems on the bank website. I've kept all the important updates current on that drive also (Windows, malware scan program definitions, etc.).