email accounts not working in outlook.com

At first, it was just an issue of receiving emails - but now it seems to be affecting all of my outgoing mail as well.  On Saturday morning (August 3), I sent out my last successful transmission - everything since then has been returned to my sbcglobal.net email - which I am in the habit of checking since there is sometimes a delay in getting emails in Outlook.com anyway.  Even though I check my emails at sbcglobal.net - I do not like to reply to them from there as they get saved on that server and do not roll over to my Outlook.com sent email.  I started using Outlook.com because I thought it would be better to be able to have them also "syncing" to my Outlook program on my main computer.  If this problem isn't fixed soon - I'm going to lose my patience and my confidence and just go back to using the Yahoo service.