I am having this problem as well, and it is happening on both of the eISY units I have (in different locations, different ISPs). Problem first started yesterday morning (things worked fine up till then). I had upgraded the firmware on both units (5.8.0 --> 5.8.3) on the day before the problem started, and was still receiving email notifications on that day after the upgrade. No other changes made on either unit. I am configured to send to a gmail server, using the default settings checked. For one of the eISYs, I got a bunch of delayed notifications late last night, then nothing since then. Nothing at all from the other eISY. Are others still having these issues -- any ideas?