I am using a Raspberry PI 3B+ for learning Python programming and some hardware design for PI3. I hadn’t turned it on for a while. Recently, I powered it up and it booted just fine. The second power up cycle, on startup, it displayed the error message: “GDBuss.Error.org.freedesktop.PolicyKit1.Error.NotSupported:Operation not supported” I noticed that when attempting a shutdown, the dialog box for shutdown appears but nothing happens when I select shutdown (or reboot, or log out). However opening a terminal window and typing “sudo shutdown now” does shut down the Pi. Additionally, it does not recognize a USB drive so I cannot move my files to another device. I did an update to the operating system but it did not help. I have created another bootable SD card with the latest Raspbian OS (Raspbian OS GNU/Linux Version 9 stretch) and it boots fine. If only I could use a USB stick to move my files from the old SD card to the new, I would be fine. I cannot find this error on the raspberry Pi troubleshooting forum nor this exact issue on this forum. Any help would be appreciated to correct the root cause of this error.