I'm afraid that I am really confused by your post.

The red message says your log-in failed, but yet you're posting?

I know that the email does keep proper case, I've just checked it with 3 different accounts, all with mixed case, and in each case the email sent the correct case sensitive password.

Is there still a problem or....?

Sorry if I've confused the issue.

Initially I could not log in using IE6, which is the browser I usually use,
Before I got your reply, I decided to try logging in using Firefox as I was aware that it might have been a problem specific to IE.

However with both browsers I was getting the message that my log-in had failed and with IE I was also getting the 'Stack Overflow' message.

After getting your message to say it was a fault you were addressing with IE, I stopped trying to log-in with that browser and concentrated on Firefox as you said it shouldn't be affecting that. After a few more failed attempts it occurred to me to wonder if somehow the case of my password had been lost/changed. So I had another attempt and entered my password as all small leters and found myself logged in and so able to post. However I have not, as yet, checked to see if I can log-on via IE.

I have subsequently been logged out and logged in again with FireFox and am still having to enter my password as all small letters to achieve a successful log-in.

Ihave now tried logging in via IE and it successfully logged me in as long as I entered my password as all small letters. Although I still got the 'stack overflow' message.