Have I made a boo boo!

Firstly I run xp home ed.
Anyway, thinking I was doing the best thing to avoid
running 2 Messengers, after downloading the latest version
6.1, I deleted the earlier version from add/remove.
Since then I can't connect at all, it keeps telling me it
doesn't recognise either my identity or/and password.

Also, (is this a coinsidence I wonder) I cannot access any
'personal' pages on the internet. for example, I can go to
my bank web site, but I cannot access my account details.

Anyone know what I've done?!!!!

I have tried reinstalling msn 6.1 twice since, and 4.7 (the
only earlier one I could find) thinking that may help.

Thanks for any help
Regards
tp