Ive been digging for hours trying to fix this. Worked for a little while, then got this error when connecting dslr. Couldnt fix it so I re installed Kstars, worked for a little while, and now its back...
Did you check what the log suggests? With DSLRs we have the problem that the device gets auto mounted as soon as it connects. This blocks the USB port.
Please open the file explorer of your choice and check if the camera is mounted. Unmount it and retry.