I receive a lot of questions and concerns from developers stating that the phpmail function is not correctly working. The problem is that 9 times out of 10 it really is installed and working and the issue usally comes from a coding error or user error (thats the thing between the keyboard and the chair). One of my core philosophies when troubleshooting issues is to break it down in its most basic form. So to verify whether or not its actually working, just create blank php page and insert the following:
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This is as basic as it gets. Really good for verifying whether or not the issue lies with your server, or you! Just run it with the following:
If all goes well you should now be receiving an email directly to your inbox. If not, then I would start by looking at your php.ini and seeing if it is disabled within the functions. You will also want to ensure that you actually have a valid MTA such as sendmail or exim and that it is indeed working and accepting connections through localhost (Or as defined by your php.ini). The mail function is built into the PHP core so there really isnt any extra enabling that needs to be happen here. If you are still having trouble, I would reccomend hopping on the IRC or Forums for your respective distro!