Are Photoshop and OS fully updated and have you performed the usual trouble-shooting routines (trashing prefs by keeping command-alt-shift/ctrl-alt-shift pressed while starting Photoshop after making sure all customized presets like Actions, Patterns, Brushes etc. have been saved and making a note of the Preferences you’ve changed, 3rd party plug-ins deactivation, system maintenance, cleaning caches, font validation, etc.)?
My computer is a Dell Studio 1747. I ran Dell's system diagnostic and everything passed. I thought it might be a stuck key, so I removed the internal keyboard and connected a USB keyboard. No change.
While testing the keyboard, I figured out the exact action that causes the problem to occur. When I start Photoshop, it works correctly until I use the keyboard for anything or switch to another open application (using the mouse). Then the problem occurs and stays until I restart Photoshop. This happens using the internal keyboard or with the internal keyboard removed and using a USB keyboard. An example: I use the Rectangle Selection tool to select an area. This works repeatedly. Then I press and release the Shift key. Then I try to select an area. The problem occurs and the tool no longer works and stays that way until I restart Photoshop.
No keyboard macro programs installed. Microsoft Security Essentials is installed. It says it is up to date and there are no problems. A keyboard test program found no problems. I have tried two USB keyboards with the same results I have 10% free on my system drive: and 15% free on my second drive.
- If I open Photoshop by opening a file, the problem immediately occurs. If I open Photoshop and then open a file, it works until I press a key as described above.
- The problem only occurs in Photoshop. I’ve tried lots of other programs, including Premiere, Audition and Illustrator; they all work correctly.
- The problem can occur without a keyboard attached. As I described above, if I switch to another application (Windows Explorer in my test) and then switch back, the problem occurs. This is true even if there is no internal keyboard and no USB keyboard.