One of our business processes is to scan checks when customers pay and attach the image as part of the record in QuickBooks. We use a sheet of paper folder to redact the numbers of the bottom of the check. Our scanner refuses to color copy some client checks, namely from a govt agency and a startup. Thankfully we can still copy with grayscale. When this happens, we have to fully power off the scanner and boot it back up again. Best I can tell it's this pattern/hologram that triggers it.

For the same reason, I had trouble making a digital copy of my daughter's birth certificate. Before I found the gray scale trick, I ended up taking a photo with our iPhone instead.