Hi Anthony Rudd
The Glossary Converter app is an easy way to export and import termbases and that process can be used to smooth out any corruptions:
It's very good at converting termbases to Excel. You can check visually for errors in Excel then convert back to .sdltb termbase format, at which point an error message may flag up anything that isn't as it should be. Then you can look it up in the error log and pinpoint where it is, correct it and convert the termbase again...
To know how to use the Glossary Converter, click on 'Learn how to use this app' on the above page ...
I hope this helps!
All the best,