[Lynne]

We aren't wondering if the cron.php file has changed - have any of your Scheduled Tasks changed? All of those tasks get called by the same file cron.php. You can't tell which one of the jobs was being run except by the time. Notice how each task is run at a different time. If the task causing the issue is run at 0:00 server time, then it is most likely the Daily Statistics Log which runs at midnight (server time) every night. If the problem is at 0:01 (server time), the most likely the Birthday notices which go out at 0:01 server time every night. So, you need to know what time the problem is happening and compare it to the jobs you have running.