Did you upgrade to MATLAB 8.2(R2014a)?. In this case the Preference Directory might not be managed properly during the upgrade process.
Try regenerating the MATLAB's Preference Directory by following the steps below:
1. Start MATLAB and type the following at the MATLAB command prompt:
>> prefdir
In MATLAB 8.2 (R2014a), the output should look like:
C:\Users\{username}\AppData\Roaming\MathWorks\MATLAB\R2014a (on Windows)
/home/{username}/.matlab/R2014a (on UNIX)
/Users/{username}/.matlab/R2014a (on Mac)
This is where your "matlab.prf" file is located. Your path may be different depending on how your system is setup. The preference directory may be hidden in some operating systems.
2. Make sure that MATLAB is closed and rename the preferences directory of your current MATLAB version and all older versions of MATLAB to something else. For example, in MATLAB 8.2 (R2014a) rename the directory R2014a to R2014a_old.
3. Restart MATLAB. A new preferences directory will be created for the MATLAB version that is launched.
If this does not address the issue, it is possible to restore your preferences by deleting the newly created directories and renaming the R2014a_old to the original names (R2014a).
