@Ted52, what I would try....
- Create a fresh library. Do not allow the structure from the existing library to be copied.
- Save to disk all of the eBooks.
- Import the eBooks in batches of 100 trying the FT indexing after the importing.
- If it fails, create a new library and try that last batch of 100 again and see if it fails.
- If it does fail, try in batches of 10 until you find what eBook causes it to fail.
I hope this works.