Email users can block email addresses, which means that they won't get emails from those addresses. If your email address is blocked by a user, a group or a site, you'll want to know about it so you can make other arrangements to contact someone. There are several ways to tell if your email address has been blocked.
Send an email to the person, group server or site that you believe has blocked you.
Wait to see if the email bounces. If it does, you will get a message back saying that the email was undeliverable. You might also get a message that says there was a server error, or that the email address you sent a message to does not exist.
Attempt to send an email to another address, just to be sure that your email account is functioning and allowing you to send messages. If this email goes through, you know the problem is with the particular place that might have blocked you.
Try to send an email to the address in question using another email account, even if you have to make a free account at Hotmail or Gmail. If this email goes through, you know there is a problem with your original email address.
Contact the person, group, or site with another email, by phone or in person and ask if they have blocked you. It could be that they did so unintentionally. It could also be that there is a problem with your email account.