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My son's emails from Gmail are all of sudden not arriving to my Cox email. We checked the settings and nothing's changed, no forwarding or blocking issues. I also had a couple people email me to test and their non gmail's arrived.
How long has this been happening? Have you found any other Gmail email not get through other then your son's? Last, does your son get any kind of bounce back message when he sends to you?
Go into Cox webmail, and change the spam blocker settings from auto delete, (this is default), to no spam blocking. This will deliver all mail to you inbox, and anything that Cox would delete, will include the word SPAM in the subject line. See if his email starts coming in.
I sent a test email from Gmail to Webmail earlier this evening that has not been received. The email isn't in Webmail Spam or Trash. GMail did not get a bounce back message.
I sent another test email from Gmail to Webmail later this evening that was received. My Spam setting was not changed from "No Spam filtering".
There may have been an earlier issue that has since been fixed for new email sent from Gmail.
Edit: The first email from Gmail was received later in the evening.
So it sounds more like a delay then a block. Can you check the headers for the send time to see if the sending was delayed or receiving?
Just a reminder... IAW RFC Specifications for email, it must be received within 24 hrs of sending. As long as the email goes through within 24 hrs, it's considered within specs.