I'm using Gimp 2.6.12 on Ubuntu 12.04. It worked fine until a couple of days ago. This might or might not be relevant, but in the meantime, I tried to plug in my usb photo scanner but since it was not recognized by SimpleScan I didn't continue to bother (will do later).
So now I start Gimp and load an image (image type doesn't matter). The image is loaded fine but as soon as I attempt to use any tool by clicking onto the image, the entire screen goes black and for a very short time, some error message appears in the upper left corner (to short to read). After that, I'm presented the logon screen (all applications are killed).
I've tried to uninstall Gimp, restart and reinstall, but that didn't help. Do you have any advice? Please note that I'm a newby (windows deserter) to Ubuntu.