Can't post my listings, get error message....help?

I posted 12 listings to ebay, but there were 4 that would not post. I got this message:

The following 4 listing(s) were unable to post because they did not pass validation and need to be edited before posting:

It does not tell me WHAT needs to be edited....and what is validation? How do I fix this? There is nothing at all different from these 4 listings than the rest of my listings that DID sucessfully post, besides obviously the photos and description (which are all spell checked and neat and appropraite, so I don't know what else the issue could be...?)

Help any one??

Thanks!