Check to see if your IP addresses are listed with nearly 70 DNS based anti-spam databases! Will your mail server be blocked by DNSbl filters?
Some Basic check:
1. Your IP is not on any blacklist.
2. RDNS is setup correctly.
3. SPF is setup correctly.
4. Do not send test messages to your Hotmail account with the words “test”, “testing” etc etc or any spam-like words or any “bad” words.
5. In your Hotmail account, make sure you have not marked the sender (which you are testing from) as a sender of spam / junk or blocked the sender.
6. Once your emails are reaching the Hotmail Inbox, send a few more “good” messages to it on and off for the next 48 hours. Make sure the body of the message has “good” content, maybe a few paragraphs. If their filter is learning from these, it should help. And of course, don’t send any junk messages to the Hotmail account.