Send mail every n days
If you have a database at the bottom, you can store the date of the last letter in the database. The script then checks to see what the latest date is in your database. If it is more than n days in the past, it sends a new email and overwrites the date in the database with the current date.
Alternatively, you can just use Cron-jobs .
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You can use a cron job. If your server has the capability.
http://en.wikipedia.org/wiki/Cron
Another option is to use an external service that runs your script once every five days.
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You need some kind of external trigger event.
Most likely a cron job to execute the task directly every n days, but since it looks like it could be a website, you can also have a cron job (or Windows task) that visits a predefined web page every n days and send the web -page by e-mail.
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