My email to users goes to SPAM folder

I have turned off email activatoin for now and enabled Admin Activation until I fix this



When someone reigsters, they don't get the registration email or they miss it actually coz it goes to their spam folder



This is a new email account that I got through my host and when I emailed them about it and sent them the headers, they said it looks fine and I need to contact hotmail, gmail, yahoo mail, and GMX Mail to remove my email from the spam



Why did they even mark it as spam? This is a new email that I have never sent anyone anything from



Any ideas guys? Anything I can change in the text that is being sent out toe members that would help fix this?

Please help.

Thanks!



I didn't find the right solution from the Internet.



References
 www.phpbb.com/community/viewtopic.php?f=46&t=2142739

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