Screen shots shortcuts disabling themselves (Yosemite) I use screen shots all the time (Cmd+Shift+4 ftw). But suddenly, I'll go to take a screen shot and the shortcut doesn't work. I go into System Preferences > Keyboard and see that ALL the screen shot shortcuts are unchecked. I check the shortcuts on, but then a few seconds later, they will be unchecked. I click Restore Defaults to turn them on, but they still disable a few seconds later.

Has anyone else had this? What could be causing it?

Even if I want to take a screen shot during this, I don't have enough time after checking the box to press the shortcut before it turns back off.

Thank you in advance to anyone who offers assistance.
If the user preferences are not sticking or been changed there are 2 possibility.

1- You have a app that does that.

2-You Permissions need repair, using the Disk Utility.- usualy Start with this step first.