Instructions which can help you:
1) Open Photoshop.
2) Press and hold "Alt," "Control" and "Shift" at the same time as the program launches.
3) Select the option to delete all current settings. All the preferences and settings you have altered will be returned to their original default.
4) Close all applications and navigate to your Photoshop plug-in folder. The location of this will depend on the version of Windows you're using. If you're using a 32-bit edition, you'll find it at "C:/Program Files/Adobe/Adobe Photoshop CS5 or CS4/Plug-Ins." If you're using a 64-bit edition, you'll find it either at "C:/Program Files (x86)/Adobe/Adobe Photoshop CS5 or CS4/Plug-Ins" or "C:/Program Files/Adobe/Adobe Photoshop CS5 or CS4/Plug-Ins."
5) Select any plug-ins not published by Adobe and follow the instructions to remove them.
6) Visit the Photoshop update page to search for and apply updates for the version you're using.
7) Relaunch Photoshop and test it.
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