I get this message when I try to publish an Adobe InDesign document online: "An error occurred while uploading the document. Please try again. Error No. 33" What can I do?

When I try to overwrite/update an existing document with Publish Online, I eventually get the following error: "An error occurred while uploading the document. Please try again. Error #33". Normally, I first see a progress bar regarding the preparation of the document, followed by a progress bar regarding the uploading of the document. The only thing being shown is the second progress bar: the uploading of the document. This happens faster than normal, after which you receive this error message: "An error occurred while uploading the document. Please try again. Error #33". Can anyone help me with this?