Sending forgot password emails

I am building a service that will have a 'forgot my password' feature. In addition to that, it will also email users when results are ready from my service.

I would like to ensure delivery of my emails so I was looking around to find a开发者_运维知识库 service that would let me send emails.

All that I've been able to find so far are services that require a user to opt-in to a list.

In other words, I've been unable to find any that will let me send customized messages to individual users.

I am currently using swiftmailer for php but would really like to find a service to do this...Anyone know of one?

Edit1: It's not that I don't like swiftmailer but more that I want to make sure I do not have my emails end up getting blocked by spam filters. Also, it would be easier to rely on a service that already has the stuff setup that Atwood talked about in that article.

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A very low volume solution that I use, and by low volume, I mean under twenty pieces per day, is to setup a GMail account and send your messages from that account. There are plenty of very simple programmatic solutions for this. Just Google for "php gmail send" and take your pick!