I had exhange working fine since Friday - all of the sudden this morning it quit working. My company allows web access at mail.XX.com - so that's what I was using as the exchange server. All of the sudden this morning, it keeps asking for a password and won't verify the account. I deleted and tried to re-enter setup - but it won't validate the account. I can still access web mail through a browser at mail.XX.com so that's still working fine - any idea why it would stop working? I thought if they were allowing the one, it would be very hard for them to block iPhone access - is that not true?