[ZombieKebab]

I've always found Calibre amazing. Calibre Companion when it works is also great.
However with a book collection of 14k+ the syncing of the two is slow and fraught with too many device disconnections to mention.
I made the foolhardy decision to upgrade the SDCard in my Samsung Galaxy S10.5 (KitKit 4.4) from 64Gb to 128Gb.
I changed the path for the books to the correct Calibre folder on the SDCard. I configured the template for the best performance.
In CC i connected via WIFI, and sent fairly small groups of books to the device in Calibre.
It trundled along at an excruciating pace with Device disconnections every 5 or 10 minutes.
After 5 days i was relieved to have sent the final book.
However when searching for Books With Missing Files in CC it returned 6988 covers with no files.
I decided a different approach. I deleted the dead books from CC, and connected to Calibre with the content server option.
3 days later i had sent the final book with this method.
Search for Books with Missing files, and yup there's thousands of them again.
AS a final test i connected via WIFI and sent 200 of the missing books back.
They opened fine, until i rebooted the tablet and they have joined the missing list again.
I really tired of how difficult and long-winded this is.
Any suggestions would be gratefully received.