i am getting the good old "assertion failed: The "id" attribute does not have a unique value" but with a twist i haven't seen -- the line number reported is -1 in toc.ncx. clearly, there's no line -1. any idea how to track down this error?

(i've already combed the toc for duplicate ids.)

thanks in advance for any advice you can share!

well. i downloaded the validator and used it locally, got a different set of errors in a different file within the ePub, repaired those errors, re-ran the validator, and all is well. the ePub still won't validate on the site, but appears to be valid based on running the jar script on my local and also based on uploading successfully to lulu.

so, now my question is -- is the online validator working??

Probably, but I never use it. Try the FlightCrew validator.