Unable to Update14.4 on my iPad 5th Generation

The last Software version that successfully updated was 13.6.1. All overnight attempts have failed. Most recent attempt was to connect tomy PC through iTunes for update. "Extracting Software" process completes. Then "Backing up iPad" runs better than 50% then message "iTunes could not back up the iPad because an error occurred while reading from or writing to the iPad" No error codes are given.

My iTune version is up to date and synced with my iPad. I restarted both my desktop and my iPad before the most recent attempt. I turned off my McAfee account. Unable to determine what to do next. Genius bars are all closed.