I can only write this is one of those common complaints.
You have to ask your email provider to check your settings. I know folk want it to be a Windows update but after decades of working Windows, I have yet to find this to be true.
I can receive messages but can't send in Windows Mail (not live mail) on Vista Home Premium. They get stuck in the outbox. It was working fine, and then this problem started after installing multiple Windows updates.

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