+xNot sure if it'll help but I had this exact same problem. After a certain date I could never get the SD confirmation email from (
flightplans@skydemon.aero) sent to my @gmx.net email account. I couldn't find any active spam filter against these confirmation emails. SD support confirmed the emails had been sent but couldn't help me find out why they never arrived. In the end I had to change the email address I was using with SD to an @gmail.com address and since then all worked fine.
My account is hosted at WEB.DE, which is the same provider as GMX !
@Tim:
WEB.DE and GMX.NET belong together with many other trade marks to United Internet, one of the biggest providers in Europe.
I just called the technical support of WEB.DE.
They told me that there is no other general spamfilter in the email path.
If they reject an email for any reason, their server always sends an answer back to the sender, indicating the reason.
He also said, that many senders do not evaluate all kinds of answers, especially in special cases.
The strange thing is also, that I do receive all confirmation eMails when filing a delay via the web interface!
This lets me think, the problem is not on my side...
So I'm asking you could you please check the low level answer that you receive from the server of my email provider.
If it helps, I will file a new flightplan and delay it later and finally delete it. Just tell me, when you are ready and lie on lookout for the answer from my providers server.