'Cos document table full' while using Comments

[Astonishing_Whirlwind5D13]

I'm working on a PDF which has a fair amount of mark up (mine) but I now can't add any more, or edit the mark up, because whenever I click on any mark up I get the error message 'Cos document table full'. It's started happening on a few of my PDFs now. 

When I've searched this issue, people seem to have problems if they're signing documents. There are no signatures in my documents, just mark up using the Comments feature. Please can someone help?

[Karl Heinz Kremer]

Which version of Acrobat are you using? I've never seen this message. How many annotations do you think you have in the document? 

[Astonishing_Whirlwind5D13]

Hello,

I've got approx 500 comments in it, and it's a 145 page document, including images. 

I'm using Adobe Acrobat DC (21.007.20099).

[Karl Heinz Kremer]

That is not a lot of comments, but it's certainly possible that the PDF file itself is highly complex (and therefore uses a lot of COS objects). I just had a script create about 3500 annotations in a document without a problem.

The first thing I would try is to do a "Save As" on the document. When you do a normal "Save", Acrobat will save an incremental update. This means that the original file is being kept intact, and new or modified information is added to the end of the original file. If you have a lot of these incrementtal updates, you might fill up the space that is reserved for COS objects (but again, I've never seen this error message before, and I've worked with PDF files for a long time). Doing a Save As will recreate the document from scratch, and that might fix your problem. So, do a save as to a new filename, and then see if you can open this file and add more annotations without getting the error. 

[Astonishing_Whirlwind5D13]

Thank you for the suggestion and detailed explanation. I've just tried that, but the problem still persists unfortunately (screenshot below). Do you have any other suggestions? Do you think it could be corrupted in some way?

[Test Screen Name]

What sort of comments are they? For instance, are they attached docs?

[Astonishing_Whirlwind5D13]

No, mainly annotations, so deletion, highlighting, sticky notes etc

[margyk64172948]

Did you ever find a solution to this? I'm suddenly experiencing the same problem--unable to mark up using comments. Just keep getting the "Cos document table full" message.

[Astonishing_Whirlwind5D13]

Unfortunately not! I tend to split the PDF into sections now if I know there will be a lot of mark up on it, which helps (although isn't ideal if you need to look at one complete document).

[margyk64172948]

Ok. I was just chatting with Tech support for about an hour. Turns out, in my case, there were restrictions placed on commenting by the creator of the document. So having to send it back to get the restrictions removed. One way to test is to see if you can add a comment to a new document that you created.

[margyk64172948]

OK. So after some digging (i.e. asking the various parties involved), it turns out it was NOT a permissions issue in my case. Even the original creator of the file was getting the same error message. Instead, it looks like that particular file was corrupted somewhere along the line. I couldn't even extract a single page without getting a Cos document table full message. Went back to an earlier version of the file, and it was fine.

[Test Screen Name]

One thing that occurs to me is that, possibly, it was signed over and over with digital signatures. You can check this looking at the signature panel in the left bar. 

[margyk64172948]

There were no signatures in the file. However there were a lot of comments. In this particular file, I could use the comment tool to make a comment, but I could not use any of the drawing tools (which I need--I'm a development editor). Also could not extract pages or do a comparison of documents without getting the same error message. And in fact, if I have the file open, then other files are affected the same way.

[Karl Heinz Kremer]

Did you try my "Save As" suggestion from above? This is oftentimes a good indication for a corrupt PDF - if the Save As fails with a cryptic error message, then there is a pretty good chance that the file is corrupt. 

[margyk64172948]

Yep, tried the "Save As" suggestion. There wasn't a problem saving with another file name, but problem still existed in the file, regardless.

[margyk64172948]

I take it all back! I started working on the earlier version of the file and after adding three comments, I got the "cos" error again. Another 1.5 hours with tech support, and the only thing they could offer was to "sanitize" the document, removing all 874 comments/edits by the authors. I told them this was an unacceptable solution. (They also told me that the "cos" error was caused by too many background calls and that I had "too many documents." because I "hadn't cleaned my system." Because other people on other systems had the exact same problem, I find it doubtful that it was just my background documents that were causing the problem.)

I tried splitting the file using extraction, and got the same cos error. I then tried deleting pages manually, and got another error. I also tried deleting all the comments manually and got the same cos error. Finally, I redownloaded the working version of the file (V3) and was able to split it by extracting pages. Oddly enough, the two split files were MUCH smaller than the original file (which for some reason was 175 MB!). I've thrown all this back to the publisher, in the hopes that Adobe will be more helpful to an enterprise client to an individual. In the meantime, Check your file sizes--I found this problem occurred in files over 100MB. (Also, not sure why the file size ballooned so much--the original file was only 70MB). Splitting a large file into separate files seems to be the only solution right now. 😞

[Karl Heinz Kremer]

You can (that is with a document that behaves normally, so all bets are off regarding your document) export all comments in Acrobat (it's under the "..." menu on the comments pane), then delete all comments, and then import the comments again (same menu). 

[margyk64172948]

Thanks, Karl. Useful to know! Does that include any markup as well?