I don’t see where you ever asked for server logs in any of the several threads on this problem that I am aware of, though you did, as Pat K observes, ask for browser error logs, which you now say are useless, multiple times. And you also sent me off on a wild goose chase in which I had to read through an entire thread trying to to find a “solution” which you vaguely referenced, only to find that it had nothing to do with my problem.
It is bad enough that this took so long to fix. Blaming that on users who were trying to get support is commpletely inappropriate.
Backup is not a cosmetic feature in WordPress, it is a crucial one, and BackWPup is now in use by far too many people for your development team to take this responsibility as lightly a as you seem tp. People are trusting you with the security of their sites. They can lose thousands of dollars in website costs and lost revenue if there is a catastrophic server failure (which actually happened to several of my clients and me during this long, long period when BackWPup wasn’t working correctly).
Fortunately, we had had sufficient knowledge/skill to download the files via FTP or through cPanel. However, many WordPress users do not know how to use FTP, or have managed WordPress hosting accounts that do not allow them to access their files directly. Also luckily, I had been following the support threads so I knew that WinRAR would show me all the files in the backups that appeared not to be there. But I didn’t appreciate that I had to install a third unzipping program at an extremely stressful and time sensitive moment.
I really like the feature set of your plugin. However, there have been many (too many) occasions during the past two years when I couldn’t recommend your plugin to my clients and had to consider other plugins due to issues. I keep coming back to BackWPup, hoping this will be the last time, and you will dedicate yourself to making the plugin more reliable, but it’s getting harder and harder to explain that to my clients.