Nokia Messaging is a great service, when it works. On several occasions Nokia Messaging simply stopped pushing my emails, requiring me to go to the Nokia Messaging website to remove an email account and add it back again for it to start working.
This time Messaging users are encountering a more serious problem, but we can’t say if this is on the Nokia Messaging side or the email services like Yahoo or Hotmail, but it’s an issue that has been going on since Thursday. Nokia Messaging user got an email saying:
Dear Nokia Messaging customer,
Recently, our email service has been unable to connect to your email service provider, preventing email delivery to your phone.
This may occur due to one of the following reasons:
1. Through your service provider, you have changed the email password of your email address. If so, you must update your Nokia Messaging service account with your new password. Email messages will then be delivered to your phone.
2. The server for your email address is down. For more information, contact your service provider.
3. You might have inadvertently changed a setting in your Nokia Messaging service account. Log in to your Nokia Messaging account on the website http://netac4.vie.hosting.nokia.com/account to determine whether your information needs to be updated.
We have yet to hear an official statement from the Nokia Messaging Blog, but we’ll keep you updated on a possible fix.
In other news, Nokia has now added support for Windows Live Messenger IM service in Nokia Messaging. Previously, Nokia’s IM services supported Yahoo! Messenger, Google Talk and Ovi communities. Do remember that the service is still in it’s early Beta and currently only works with the E71, E75 and E63. The idea is that Nokia Messaging will become the one-stop place for IM, Email and Social Networking. Windows Live Messenger for Nokia Messaging can be download here.
The one stop place for everything messaging for your Nokia device can be found here.
Nokia Messaging down and support for Windows Live Messenger

I was getting those same emails too in the last week, and not able to sync my N82 with my hotmail. I removed and then re-added the hotmail account, and now so far it seems to be working again…
I’ve had exactly the same problem although removing the mailbox settings and setting up again didn’t resolve the problem