THIS IS THE REAL DEAL.
This is the issue...at least it was for me. And it makes sense:
* Why do some people get this and others don't despite the same OS?
--> Not everyone has Non-ASCII characters on their Filesystem.
* Why do some devices have this issue and others don't despite being owned by the same person?
--> Not all exact content is on all devices.
* Why is this fixed for some people by "deleting their largest apps" but not for others?
--> Because the larger the app, the more data that app stores, meaning the more likely that data is to hold a character that will corrupt the backup.
To be clear:
Using iMazing - The FREE Version (not a promotion) - I backed up my iPad via the software with the console open and with a search string of "No operation found for path"
The moment the backup broke iMazing's console showed me this exact path and I noticed that an e-book had an author's name with an accented "a" character in the title.
I went into my e-book software, renamed each e-book by that author to remove the accent "a" and replaced it with a normal "a", and re-ran a backup.
My iPad now backs up without a hitch.
Again:
* I did not delete any programs.
* I did not delete any data
* I did not reinstall any applications.
* I did not have to back up with Airplane mode or reset network settings or any other of the many "fixes" for this problem.
* The ONLY thing touched during this entire process was to remove the Accented Character from book titles through renaming.
I will re-link the document that everyone needs to pay attention to here:
https://imazing.com/blog/ios-10-3-3-device-disconnected-error-during-backup-fix
This solved my problem, your mileage may vary. That said, if your device is failing backup at about the same place every time it backs up, and you've tried on multiple computers and with multiple cables, there is a HIGH likelyhood this is a fix...
This is not a hoax, this is no joke, this is the real deal.
Massive Kudos to iMazing and those who tracked down this issue.
