Comment 9 for bug 910964

I think I am having the same problem, with a Fujifilm F100.
I'm running 12.10 3.5.0-22-generic and shotwell 0.13.1

I also get "Shotwell Unable to lock camera: Unspecified error (-1)"

I just upgraded from 12.04 and this is the first time I've tried to import from the camera since then, and the first time I've gotten the error (that is, it worked on 12.04).

I installed it ghpoto2 and got the same error as the OP:

~$ env LC_ALL=C gphoto2 --debug-logfile=logfile.log --debug --list-files

*** Error ***
PTP I/O error

*** Error ***
An error occurred in the io-library ('Unspecified error'): No error description available
*** Error (-1: 'Unspecified error') ***