I have a shopping site that own thousands of members. i would like to send them a promo email , there are 2 problem now: which is better? html or text format? How to avoid my email be filter into spam box?
for avoiding the spam filter: avoid the red flags -- all caps, strange punctuation, exclamation points, using the word "free" , "win" , or "congratulations" ... etc.
or you can post to your site on first page. add this address to your contacts to receive latest offers in your INBOX. I should say that the best is txt because if you send html, even if it gets inbox, gmail and others won't display your pictures.
html, before you send out email check for spam keywords, google for free services,.. also include unsubscibe link,
what mailing program are you planning to use? one thing to do is set yourself up an account at each major free ISP (hotmail,yahoo,gmail, etc) and at least 1 box that uses spam assassin or similar filter. then just simply test your email into your own accounts and make tweaks until you see the desired results. as suggested above, making your content work is common sense (no words like free, viagra, etc).
Well, all the answers to i read here are all belong to the very-old way of preventing spam. The first things you need to do is to fix your networking parameters. Find a good smtp testing site and perform all kinds of tests (use paid service - it is cheap and MUCH better then the free ones). This will probably get you to configure reverse DNS entry (PTR record), an SPF record and few essential email accounts such as postmaster. Now find SMTP spam blacklist checking service (the free ones are good) and check your IP address. If it is listed in too many spam services then you should contact them and find out why it is blocked. If it is because your server resides in a "bad neighbourhood" then you might need to move it or at least move your MX records to a better neighbourhood. Now that you fixed all your networking issues, 90% of the problem is solved. You are not running from a spammer network and you identify yourself (SPF & PTR). The next step is to have a look at this list of spam criteria (the more score - the more important to avoid that problem) and make sure you score less than 5. One simple way to find what is your rank is to send the mail to a server that checks that and report the score and the reasons. If you need help with that contact me via PM and i will set up an account for you on one of my servers so you can test your email and see it's score. This is of course valid ONLY if you are sending the mails to a legitimate list and not to a spam list... Now the last thing: If you try to do this in order to be able to send spam, i suggest to you to give up now. You are wasting your time and efforts.
What may be added to what redhat77 already emphasized is that you should take very much care what links your emails will contain. Always check the links in order to be sure that they are not from domain names listed on blacklists (Don't assume that only spammers' domain names are listed on blacklists. There are some autoresponders domain names that are blacklisted and a lot of other domain names that belong to legit businesses).