I have had problems with installing images to SD Cards and in the end I have found
sudo dd bs=4M if=/home/rob/Applications/RaspberryPi/Ubuntu_Mate/ubuntu-mate-16.04-desktop-armhf-raspberry-pi.img of=/dev/sde
to be the most reliable. Using image writing options in applications like "disks" etc just did not seem to work. Though I continue to use GPartEd and Disks to prepare the SD cards to begin with. If the above CLI does not work, I would be 99% confident it is the card. (Make sure "sde" drive identification is correct for your setup).
I had problems with updating UMate on my RPi3 and solution was I had to reduce the ROOT partition, so I could create a second, larger partition that I copied all the original BOOT partition to. (ie on a 32Gb SD, copy BOOT files to hard drive, reduce ROOT by 200Mb [this may take ages], delete BOOT, create a new BOOT partition in the new free 200Mb space, and copy all the BOOT files back onto that new partition. Just ignore old BOOT space. It has worked well. My RPi3 has run Apache II 24/7 for last year and has been very reliable).