Unable to mount this device error when using usb stick but not always

Out of the blue I started getting this error msg. Using PCLOS 64bit Unable to mount this device. Potential reasons include: Improper device and/or user privilege level Corrupt data on storage device Technical details: org.freedesktop.UDisks2.Error.Failed: Error mounting /dev/sdk1 at /media/Lexar: Command-line `mount -t "vfat" -o "uhelper=udisks2,nodev,nosuid,uid=0,gid=0,shortname=mixed,utf8=1,showexec,flush,noatime,shortname=lower" "/dev/sdk1" "/media/Lexar"' exited with non-zero exit status 32: mount: /mnt/Lexar: /dev/sdk1 already mounted or mount point busy. It's random and sometimes suddenly goes away. I've tried it with a variety of USB sticks. It happens as user and root. Anyone have any idea what this might mean. I've also noticed uuidd doesn't start, claiming "failed to open/create /run/uuidd/uuidd.pid" Thanks for any help. Kate