Other than the fact that your server is DEAD SLOW (about 50 –yes, fifty!– times slower than this site's run-of-the-mill VPS) there is no bug in the software (if it were a bug, it'd be repeatable all the time). I am actually able to see your backup log file without a problem (a couple of times it timed out with a 500 error, but I am always able to use the download button). I just have to wait a few minutes after the backup fails.
And that, ladies and gentlemen, is the observation which breaks the case! The backup fails because your host triggers what is commonly referred to as CPU usage limit. The backup is a resource intensive process. Your host is GoDaddy, affectionally referred to by yours truly as CrapDaddy. If I had a dime for every GoDaddy-related issue I've seen with my and others' software I'd probably be swimming in gold coins like Scrooge McDuck. *sigh* This host is known for cramming 3,000-5,000 sites on a single server (industry average: 1,000 sites per server; quality hosts: 100-500 sites per server). In order to allow all those sites to all run on a single machine they impose very strict CPU usage limits. If you bust them, your account is suspended for a few minutes.
Unfortunately, the only solution is to move to a quality host. I strongly recommend CloudAccess.net, iRedHost or Rochen. They might seem a tad more expensive, but they are faster and much more secure than GoDaddy.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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