Now, I'm left wondering if should try upgrading to 7.0 and inheriting my 6.1 backup from there. They suggested updating to the 6.1.0.372 beta, which turned out to have the exact same bug. I was rather happy with my findings and shared them in plenty of details with support (including log excerpts), but instead of a 'thank you and here's some free months of service !' response, I got 'meh, this log file is irrelevant', and worse: no promise to escalate the issue (until I insisted a second time). Notice the extra 's' ? Pretty obvious typo and one that could definitely explain the failure (client can't confirm that the selected backup is eligible for inheritance, bails out) I quickly found a potential smoking gun (in bzbmenu.log) : a spelling mismatch in an XML attribute name between the server response (support_inherit='true') and what the client was expecting ('ERROR could not read attribute named supports_inherit'). That's where things get interesting : I became frustrated with the canned responses from support and decided to delve into the client logs myself. Well, we never managed to get the inherit process to complete : it failed with 'ERR_error_unknown' every time. Support advised me to wipe /Library/Backblaze*, reinstall, then inherit the existing backup.

I went ahead and did that but got 'Installation could not complete, please contact support' each time. Here goes : a few days ago the Backblaze Mac client started prompting me to upgrade urgently to the latest version (6.1.0.370). In case someone at Backblaze is reading this : I had a less than ideal experience in the past couple of days, trying to report through normal support channels a potentially critical bug breaking the 'inherit backup' feature in the Mac client.

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