How are you tagging the content in InDesign? Using the Tags panel and Structure pane?
Do you save on a server or local? Try local, if this would work, you could have server problems.
If you Print to PDF you will not have anything interactive, such as links, bookmarks, tags. Keep trying with File > Export. It may or may not be the tags that are causing the problem. It could be a font or an image.
Try Exporting one page. Does that work?
Try half the document.
There are two titles at www.lynda.com that you might want to watch. One is comprehensive by Chad Chelius who just answered you above.
The other was just published on a couple of days ago by Mike Rankin. It is 3min 29sec and is part of a longer title about interactive documents. It's very brief and gives a quick summary.
Yes, that's how I'm tagging it.
I'm working locally.
Hmm... so, exporting one page works fine. Exporting half the document didn't. I started decreasing the amount of pages and noticed something odd.
At a certain point (5-10 pages), I was still getting the error message, but then when I moved on and started trying something else, the PDF opened.
In fact, as I was typing this, the full 178 page PDF opened with tags and bookmarks intact. Which actually explains why I was also having problems saving the next testing version with the same name, even after it was deleted (I got the "this is in use" message).
So, assuming this is a size issue, how on earth can I go about optimizing it so it doesn't take 5 minutes to load?
Todd, tagging content via the structure pane for PDF Accessibility is the long and arduous way to doing things. As of InDesign CS 5.5, Adobe made the process much easier. As Jane mentioned above, you can watch some courses on Lynda that walk you through the process step by step.
In summary, the new approach would be to:
1. Use styles to format your text.
2. In the style definition specify the mapping of the style to the appropriate tags
3. You can add alt text in the Object > Object Export Options dialog box with an image selected.
4. Use the articles panel (if necessary) to specify content order in the exported file.
5. During export, choose "using Articles panel" instead of structure or layout.
Unfortunately, I wasn't involved during the creation of the document, so I was retrofitting everything to accessibility guidelines.
Do you have any tips on optimizing the document to decrease PDF load time?
Further testing shows that the error message is only displayed while the PDF is still exporting. 80,000 KB files apparently take a while to export. Who knew?
Once the file has been fully exported, it can be opened and browsed as normal (with a bit of lag on open and navigating, which is to be expected with the size).
I'd still appreciate tips on how to optimize it to decrease the size and export time.