When trying to email from a web page I am presented with a dialogue stating:
"Could not perform this operation because the default mail client is not
properly installed". When I click OK, circa 60 web pages are generated
stating "Action Cancelled".

I have carried out all the normal checks and tests:
- Internet Options / Programs states OE as the email client.
- I have run "C:\Program Files\Outlook Express\msimn.exe" /reg

However when I try to set OE as the default mail provider in
Tools/Options/General in Outlook Express by clicking the button, accepting it
and closing the tab, it does not keep the setting.
Likewise when I select Outlook Express in Set Program Access and Defaults it
reverts back to "Use my current email program".

I am running XP SP2 and this only happens on one of my accounts. The other
account operates ok and I cannot see the difference between the two.

Any advice would be gratefully received.