Canon camera problem

[Jan Willem Stumpel <jstumpel@planet.nl>]

Although I did "nothing" to the system (apart from regular Sid
upgrades) I suddenly cannot download pictures anymore (using
gtkam) from my Canon (powershot A420) camera. This is not a
"mounted storage", but a "PTP" type camera.

The system can "see" the camera alright (it is listed in
/proc/bus/usb/devices; when it is switched on a message in
/var/log/syslog appears, etc.) but apparently cannot "open" it
anymore.

In gtkam a message appears:

   Could not get file list for folder '/'

  An error occurred in the io-library ('Could not claim the USB
  device'): Could not claim interface 0 (Operation not permitted).
  Make sure no other program or kernel module (such as sdc2xx,
  stv680, spca50x) is using the device and you have read/write
  access to the device.

The trouble is that I do not understand anything of this.

Any suggestions?

Regards, Jan