There was a recent issue with the Report Writer reports printing a black box instead of an image. This problem was the result introduced by a Windows update and quickly acknowledged as an issue by Microsoft.
This is an example of how the standard report looks when the bug is present:
The Dynamics GP Support and Services Blog posted about the problem on the 12th March and have posted regular updates on the progress of the investigation.
The latest update on the 22nd was that a new update had been released which fixed the problem for legacy OS’s like Windows 8 and Windows Server 2012 which follows current versions having working updates available from the 19th.