I'm currently moving a newsletter from Yahoo groups over to my own mailing list. I'm having the problem though that I think the emails will get into the junk box and not in the inbox.

What can be done to make sure that they get in the inbox? There are like 4250 subscribers that will be imported so it's quite a nice amount. And I don't wanna use Aweber or whatever, all on a custom newsletter script. Should I buy an email package on a host or can I go to whatever host?

Thanks in advance