Cannot send emails from Comcast Account

There are several postings on this subject, but I will repeat the problem and the only solution I have come up with. The problem : Comast is blocking sent emails from any account they determine to have sent more than 1000 emails in a given day. They do this to try to limit spamming as much as possible.  I know this is fact. They only block the sent emails if they are coming from third party software, like Outlook or software on phones or tablets.  I can go directly to webmail or use my phone off wifi, and sending emails works fine all the time. So, the only way I can get around it is to power off at night. Then the next day, sending emails works until about 3:00 PM that day. If I forget to power off at night, I cannot send emails from Outlook the day morning until about 7:00 that day. It appears to me that when my computer is powered on, Outlook is sending messages, or continuously trying to authenticate to the Comcast server, or someone is using my computer to surrepticiously send spam type messages. Anyway, I don't get much luck with Microsoft on the issue, or even Comcast. If anyone has experienced this and has a solutuion other than powering off, I'd be happy if you would share.