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The document couldn't be loaded


We decided to move the Groupdocs viewer into an iframe to isolate your styles and javascript. Unfortunately I’m now getting this error message when I try to annotate the document:

The document couldn’t be loaded…

This is happening in the call to /document-annotatin/CreateAnnotation which returns the following error message:

{“message”:“Value cannot be null.\r\nParameter name: key”}

I have compared the request json between a working and non-working version and one does not have the connectionId property:

Working request json:

Non-working request json:

If the missing connectionId is the problem, do you know why this might be happening?


Hello Jason,

We are sorry to hear that you have such issue. Unfortunately our developers cannot define the reason of this issue without additional details. We need some example which can be used for reproducing, investigating and resolving this issue.