Posts made by Martin Dougiamas

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I don't think it's PHP5 ... moodle.org uses PHP5, for example.

Perhaps the services you are trying have some sort of spam control?

Try turning on all the debugging under Admin > Server > Debugging (especially debugsmtp) and then run cron.php from the command line ... you might see some useful feedback from Moodle about the error.
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I spent days nutting out times in Moodle originally and even then PJ rewrote a lot of it - they are a real headache to think about!

Most of the timestamps in Moodle are generated using time() which yes, is GMT. (ie the number of seconds since 1/1/1970 0:00 in England).

You'd use mktime() if you were generating a GMT timestamp from some arbitrary date/time (eg in the future) expressed in your local time zone.