For the last month or so I keep getting this message when sending outgoing emails from my home office to clients and "approved" recipients. This just started happening about a month or two now. I send a message and a Norton message appears - #550 5.7.1 saying that this message has been determined to be Spam. It is NOT spam.
I don't know why this is suddenly happening. I then open up the message, add the recipient to my Approved Safe List and then resend. It iwll then sometimes go through or it might bounce back again.
I went online with Verizon where their tech person took control of my computer and wouldn't you know, I could not make it happen so we were not able to solve it. However, it keeps happening with a high level of frequency.
I read your blog comments and see that it might have something to do with authentication but I am unsure what do to. I am a sole proprietor business and simply have one computer and a laptop. No server.
Please advise!!!! I am very appreciative.