emails are not being received by recipients even though email is in sent folder
I'm having issues with multiple recipients not receiving emails sent from my *.comcast.net account. The emails appear in my sent folder. I'm using Outlook as my client, but the same is happening when I send from the Xfinity Web app. If I aske for a delivery receipt I do not get confirmation it was delivered. I suspect Comcast is blocking the outgoing email. Recipient has checked his spam/trash and security filtering and it is not there.
Any suggestions. I've sent both to his domain account email and his *.live.com email and same result, he doesn't get it.