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Parallel processing error

If two clients open the same document (same SessionID), a processing folder is created with the current timestamp (e.g. 2015-12-22T08_17_21).

If the clients open the document at the same time (second), they will both access the same processing folder and one client gets an error.

Can you ensure that there is no conflict on simultaneous document access?

Many thanks in advance!


We are sorry to hear that you have such issue. Could you please share with us the error and Annotation library version. Also we have checked your behavior (by collaborating the same document via two users in different browsers) and all work well for us.

Thank you.


we use GroupDocs.Annotation 2.1.1 for .NET.

You have to open the file in the same second. So the processing folder will be the same for both browser sessions (that’s the cause for the error - you take the timestamp second as processing ID).

Then the resulting error is shown in a jerrormodalText window in escaped html code.

You should display these errors in rendered html (or plain text) by the way! It’s unreadable this way.

See error details in attached file.


Thank you for haring the issue. I have tried to reproduce it but unfortunately I can’t. As you see on this screencast I have opened the same document in two browsers (under anonymous user in the left side browser and user with name “test” in the right side browser) and tried to access this document (by refreshing the web page) at the same second - there is no any errors. Since that could you please prepare similar screencast which will show the reproducing process and error, if possible in English that I can share it with Product team.

Thank you.

Hi Pavel,

thank you for sharing your screencast!

I will investigate a bit more and prepare a setup.

See the english error message attached.

Hi again,

Thank you and waiting for additional info from you.

Best regards.

Hi again,

I can only reproduce the error with .EnableAnnotationsAutoImport(true) enabled. Without that setting everything works fine.

So use your sample project with auto imported annotations and a large PDF with annotations on it.

Then open it with the same or different user at the same time in two browser windows. This will provoke the error.

I attached the english error in my previous post.


Thank you for this important info. Now I was able to reproduce the issue and have created a bug ticket for our Product team. When they resolve it - I will notify you here.

Sorry for the inconvenience.

One year passed.

Any progress?


Sorry for the delay. The issue is resolve in the latest GroupDocs.Annotation for .NET library. The new Annotation library is totaly rebuilded and has nathing with the legacy one (2.x versions). This new generation is UI less so you will need to develop you own one or use it from our example project. Please migrate to the latest version, for how to migrate please check this documentation.

If you will have any issues or any questions about the migration - please feel free to contact us.

Best regards.

Thank you Pavel!

I assumed I’d get informed when this issue is resolved, regardless of the version.

Best regards,


Hi Phil,

Sorry for the inconvenience.
If you will need any help - please create a new forum thread.

Best regards.