In your first post you showed a screen capture of the MyCloud.com web portal. As indicated remove the “_” from the file name and the MyCloud.com web portal should show the icon of the JPG file.
As to your comment about unplugging the drive and plugged it back in again, what does that mean? Did you turn the My Cloud off and back on? Did you unplug the network cable from the My Cloud? Or are you talking about unplugging a USB external hard drive from the My Cloud?
Windows 10 is having some issues with the My Cloud since the Windows 10 November update. The main issue is the My Cloud does not show up under the Computer section in Windows File Explorer. If this is the case see the following thread which is tacked at the top of the subforum where several possible workarounds are discussed.
https://community.wd.com/t/compilation-of-windows-10-methods-steps-and-solutions/142576
