Hi, Sophie --
I phoned Bank of America's tech support a few days ago and was told that there was, indeed, a problem. Emails to them since then have been met with vague replies, including instructions that won't work because the problem isn't at the users' end.
This apparently is not just an issue with MSN Explorer (which may be detected on the BofA website as Internet Explorer 7; IE7
is supported by BofA's website). There is a website that reports corporate websites having problems or outages and has logged literally hundreds of complaints from all over the country on this issue.
Different browsers may or may not work, depending on where in the country you are. For instance, I (on the East Coast) can't sign in on BofA using my MSN Explorer 10 (this was never a problem before). However, I
can sign in using IE8. According to postings, users in other parts of the country can't sign in using IE8. Some have also tried (at BofA's suggestion) installing IE9, Chrome, Firefox and other browsers, only to find that the problem persists on those as well.
BofA changed the "design" of its challenge question and passcode entry screens recently; that's when this seems to have started.
I hope they get this worked out soon.....and that it doesn't get worse!