Background: Sometimes Photoshop can exhibit odd/erratic/weird behaviour.
The first step is to make sure that you are running the latest version of Photoshop, by applying the relevant updates for your version of Photoshop listed on this page:
This behaviour can sometimes be overcome by resetting the Photoshop Preference file, or individual Tool Preferences.
The procedures outlined below are the most common methods of removing the program preferences file.
Q: I am experiencing weird behaviour in Photoshop. - How do I delete / reset my preferences?
Photoshop versions after 6.0 (including 7.0, CS, CS2 ...CS6):
A:If a tool is behaving erratically, first try resetting just that tools preferences, via the method outlined by Len Hewitt in the post below this one.
If you have larger troubles, hold down Alt, Ctrl, and Shift keys (Mac: Command, Option, Shift) while starting up Photoshop. A dialog box will appear asking if you wish to delete the preferences/settings file.
A2: You can also simply search your hard drive for a *.psp file and delete it. It will be called something along the lines of "Adobe Photoshop X Prefs.psp".
Under Vista or 7, look here:
Users/[Username]/AppData/Roaming/Adobe/Adobe Photoshop [version #]/Adobe Photoshop [version #] Settings
Under Win 2k/XP the preference file will be found at:
%windir%\Documents and Settings\[username]\Application Data\Adobe\Photoshop\[version #]\Adobe Photoshop [version #] Settings
[NOTE: You need to set Window's Explorer Options to "View Hidden Files and Folders" to display the Preference file]
Photoshop Versions 5.5 and earlier:
Search for photos*.ini and delete (the file will be called photos followed by the version number - i.e photos55.ini for Photoshop 5.5, photos40.ini for Photoshop 4.0)
Resetting the preferences will restore Photoshop settings to factory defaults.
If removing the preferences files does not resolve the problem you should check the Photoshop Support pages for further guidance.
Note that it is possible to keep a 'healthy' copy of the Preferences file, so that you simply overwrite the preferences file if needed. That way you won´t have to re-adjust your preferences in Photoshop after a Reset.
More information on Photoshop preferences can be found at:
Tech doc, CS5:
Tech doc, CS4:
Tech doc, CS3:
Doc on manually removing Bridge preferences and cache: