if i want to modify the Newsletter system in TBH_web that is the system can do send attachment files and send letters in group such as Country, age of customer, gender. How i can do this?
                                                         thank

Hi,

Let me break down your post into two questions:

1) Sending letters to groups
2) Sending attachments

1) You can easily add user roles, and reference those in your code (similar as to how Marco checks whether users are editors or administrators, etc.
2) I'd strongly suggest you not to use attachments in newsletters. Attachments might be filtered out by mailservers on the other end, and the majority of people with any basic understanding of computer security would delete any newletters containing attachments (at least, I would).

Cheers.

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