Email technical problem with Outlook.com

My desktop PC has Win 7 Home Premium os.My ISP is Charter communications. I use Windows Live Mail as my primary Email program with a charter.net email address. I also have email addresses for Gmail and Yahoo. I only have those because you cant have a Yahoo or Google acct without having an email address. Finally i have an Microsoft account which includes Outlook.com...again whether you want it or not.
My Outlook.com email address is my MS user ID @outlook.com

Several months ago something happened to my Outlook.com email program . Whatever it was resulted in my receiving the following message with every email message i received from anyone on my contact list."This message was undeliverable due to the following reason"..Each of the following recipients was rejected by a remote mail server.
Recipient: my user id@outlook.com
Reason:Requested action not taken: mailbox unavailable.

I have tried every way i know to figure out how to fix this problem. My ISP says they cant help me because their own propietary email program is working perfectly for me. I would prefer to continue using Windows Live Mail ..i dont want to use Charter's email program.

As a last resort i cancelled my Microsoft acct which includes Outlook.com. They make you wait 60 days in case you change your mind. I could NEVER get any help on this problem from Outlook.com so i figured if i closed the entire Microsoft acct ,including Outlook.com, the problem would go away because there would be no more email address...my user id @outlook.com. Now three days after the acct was closed i continue to get the SAME MESSAGE as i quoted above. I have no idea what else i can do except to format my hard drive ,reinstall Win7 and start over which i of course dont want to do.

Maybe if i open up a new separate Microsoft acct with a different email address that would work? Or maybe i could write to Microsoft for help since i cant access any help on their website?

I have a feeling this is a simple problem,but i have run out of possible solutions so if anyone out there can help me,or direct me to someone who can i will really appreciate it. Thanks very much.

I get the error message when i send an email, but the recipient always receives the email message.

my friends get the error message when they send me and email, but i always get the email message.

the error message pertains solely to my outlook.com email address.....id@outlook.com...NOT GETTING THE MESSAGES...even though I DO NOT INCLUDE THAT EMAIL ADDRESS IN MY SENT EMAILS, nor do my friends include that email address in the emails they send me.

my outlook.com email address is somehow being automatically included in messages i send that i guess emails sent to me by my contacts. I actually receive all kinds of emails from other sites like newsletters, etc without the error message showing up with the message. Other examples would include sites like ebay, amazon, companies i purchase merchandise from, sport site newsletters, online newspaper i subscribe to etc.This suggests to me that i am only getting the error message when someone i have sent an email to in the past...USING THE OUTLOOK.COM EMAIL ADDRESS...is involved. I did use that email address occasionally up until about 3 months ago,but when i tried to find out how to uninstall outlook.com i couldnt do it, thus i finally closed my Microsoft acct hoping it would eliminate the Outlook email program as part of that. Unfortunately, even since closing the Microsoft acct i continue to receive the same error message tagged to my Oulook.com email address.