We are also still having this issue. It seemed to be resolved this morning, but then started up again this afternoon.
Just an FYI for anyone at Constant Contact: we get email from Beckers Hospital Review. None of the embedded links work because O365 says it's a malicious site (r20.rs6.net). Allowing that url in 365 didn't fix it because it's a re-direct to Constant Contact, not a link directly to the web site. So any of your customers who use O365 aren't going to be happy about that.
Welcome to the Community! Thank you for reaching out to us. We are currently working to get this issue resolved and we apologize for the inconvenience! You will be notified when the issue has been resolved.
We appreciate your patience. If there is anything else we can do for you please let us know!
We are also having problems with this -- we have members who cannot register for our events because they are being blocked. Please add us to the list to let us know when this is resolved.