We have found that some firewalls or web-shield software may cause issues with the screenshots.
This type of software can cause a number of the functionalities of Hubstaff to not work, like the screenshot capture; for example. One of the symptoms users usually experience are blank or black screenshots on the Activity screen. (As shown above)
All past occurrences have been caused by web-shield or anti-virus software such as McAfee. We found that a software called Webroot and VirtualBox may also trigger this behavior. We suggest you uninstall or disable any type of identity shield software in order to show screenshots correctly.