Are you accessing Document Cloud on web or through the desktop application Adobe Reader DC?
If you are working on web then you may check with a different web browser that what you are using currently.
If there is any internet security software installed, then you may turn it off for a while.
[Antivirus software can help protect your computer against viruses and other security threats. In most cases, you shouldn't disable your antivirus software. If you have to temporarily disable it to install or activate other software, you should re-enable it as soon as you're done.]
If its a desktop application Adobe Reader DC, then you may check with a different file than the one which contains the images in it?