my activation emails went into the spam filter I checked the mail and it is showing that both your domainkey and dkim are neutral with no sig and I'm not sure if you have an SPF record or not. If you have access to your DNS I would firstly place an SPF record as both an SPF and TXT then I would ask your email server supplier for a copy of the sig files required and place them into your DNS zone file for both domainkey and dkim although if I remember rightly they are often the same and can use the same key. Your email supplier or DNS supplier should be able to help you with the format to insert in the zone file. If it is your own server on your own IP then you may also not have a RDNS pointer for the mail server, I run a mail server from the same IP as I host domains so I set the pointer to reflect the mail server as it does little for the domains and works best this way. Aside from that you have Hotmail, in addition to the above hotmail will depend on your IP address for mail sending and if it has any history, if it is a known supplier with a good record you should have no issue but if you are using your own IP it may be unknown and take some time for Hotmail to accept it as a legit IP, or worse it may be an IP on a black list but that said my email would have mentioned this and it doesn't.
Hope that helps
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