Free Support Forum -

High failure rate for document viewer


First, let me start by saying you’ve made some beautiful tools. I’m really excited about the potential for integrating these into the product I’m working on.

So I’m working on a prototype for and integration with your viewer, and have been seeing the attached failures frequently. I wanted to make sure it wasn’t my code, so I took the example from and tried uploading using this as well. I’m still seeing the error at least half of the time I submit a file. I’ve been trying mostly with various PDF and DOC files, and have attached an example PDF on the chance that the files I’m using have something to do with it.


Hi Bruz,

Thanks for getting in touch,

We've managed to reproduce the issue that you are seeing and we're currently investigating, we aiming to have a fix ready for this ASAP. We rolled out a new production release last Friday which contained many optimisations regarding how documents are handled which looks like is has introduced some issues with larger files (instead of processing the whole document we now split the document into pages and process in parallel).

We've added some testcases so that we can trigger this issue on production, so once we track down and fix the root cause will be monitoring to ensure that there are no regressions.

These optimizations will also allow us to farm out individual pages for processing to allow us to scale GroupDocs alot easier.

Best regards,


Developer Support Lead

Hi Derek,

Thanks for getting back to me on this and working towards a fix so quickly.


Hi Bruz,

You'll be glad to hear that we've resolved this issue, and a hot fix has been rolled out to production.

The issue related to duplicate files name in different threads, where a thread was trying to lock a file which was already locked by another thread.

Hopefully you should no longer see this issue.

Please feel free to get in touch if you have any other issues,

Many thanks,


Derek Hyland
Developer Support Lead