every time someone sends me an email they get a mail delivery failure with *** Email address is removed for privacy ***

but i do receive the message.

My son is epileptic and has been bullied by a teacher at school.  I emailed a formal complaint letter which the school have told me they never received.  It was in my sent folder, it did not bounce back, I did not receive any failure notifications.  I am sure the school have deleted the emails as they did not want to deal with the issue in writing.  I need to prove that the email was received by their server.  Please can someone help me.
Everytime I try to install Windows Essentials, I keep receiving Installation failure error message.  
Everytime I try to install Windows Essentials, I keep receiving Installation failure error message.  
 I constantly get the error message: The server for the account gmail returned the error (ALERT). Too many simultaneous connections (failure) Your username/password or your security settings may be incorrect. Would you like to try reentering your password. I reenter my password and it keeps pooping up. How do I get rid of it?
Error Message
 I constantly get the error message: The server for the account gmail returned the error (ALERT). Too many simultaneous connections (failure) Your username/password or your security settings may be incorrect. Would you like to try reentering your password. I reenter my password and it keeps pooping up. How do I get rid of it?
-Outlook 2011
-Exchange 2010
-Chronic password error
I was trying to send a letter with 350 to 450 words in it, and I got a delivery failure notification.....What length limits are there on hotmail?
We had a catastrophic failure on a dell that was 3 years old and had to reinstall everything. When we log in to Windows Live Mail, we have no history. There are no signs of emails received or sent. Sorry if this is a stupid question but is the email history stored on our PC (now wiped)? We thought it was remote so you could view your Windows Live Mail anywhere in the world. As well as trying to view Windows Live Mail on the old PC, we are using a new laptop too. Thanks
i can send from hotmail to my friends isp email but when she replies or tries to send message she gets failure to send message