More information about the problem and system you are using would give us a better chance to help you.
If the following things don't work plese supply PS version, OS, what is happening and full error message.
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Hold down Shift+Alt+Ctrl (Shift+Option+Command on the Mac) this will reset the preferences for photoshop back to factory settings.
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If not i found this.
TROUBLESHOOTING PHOTOSHOP STARTUP
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The most tenuous moment in Photoshop is while it launches and initializes all its support files, such as fonts, device profiles, and so forth. In fact, a common startup error occurs while Photoshop initializes the ICC engine.
In almost every case, a simple procedure will expose the culprit. First, move all the .icm and .icc files from the Windows, System, Color directory to a new folder. Then, restart Photoshop. With all of the ICC profiles removed, Photoshop should launch.
Now for the tedious part. Shut down Photoshop and move, one at a time, only the profiles you need. After you move a profile back to the Color directory, launch Photoshop again. Continue until Photoshop bombs during startup. The last file you move is the culprit. Most likely, this means the file is corrupted.
Manic
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I've broken it again !!
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lee.gale@virgin.net