I assume when you click on the error it is taking you to the location where the error is. Not seeing the document it is hard to tell... do you have a multi-page document and when you click on the error does it take you to the location where that problem is?
There are several things that could cause this problem. The Figure or other tag that contains the alt text must have content. It cannot be an empty tag.
It also cannot have another Tag inside of it containing the content. There must be some actual content directly within the Tag with the alt text, not nested inside another Tag, if that makes any sense.
Or, there may be another Figure Tag that has no content. That, too, will generate an error.
If neither of those suggestions work, if you post the file I can probably find the problem.
Acrobat 11 has a nice feature: it will show you the offending tag or content item. Download the trial version, you will find your issue in a flash.
I am having this same issue using acrobat pro 9 and I was hoping you could help point me in the right direction for figuring this out.
I have added alt text to every image/caption (I selected the fig/caption option in the touchup reader and added an alt text) but it still says I have to add alt text to some figures. and not all of them, only a small handful. ???
any help would be greatly appreciated.
thanks in advanced.