MATLAB: Do I receive an error when I invoke a new Editor session in MATLAB 7.6 (R2008a)

MATLABprologxml

When I invoke a new MATLAB session, a Fatal Error is reported. The error message is as follows:
 [Fatal Error] :1:1: Content is not allowed in prolog.
However, the editor does start up and work correctly. Subsequent calls to the editor do not produce this error.

Best Answer

The error is an XML error, so there is a problem with one of the saved status settings. Regenerating the preferences solves this issue.
To regenerate your MATLAB preferences, do the following:
1. Start MATLAB and type the following at the MATLAB command prompt:
prefdir
In MATLAB 7.0 (R14), the output should look like
     C:\WINNT\Profiles\{username}\Application Data\MathWorks\MATLAB\R14 (on Windows)
     /home/{username}/.matlab/R14 (on UNIX)
     /Users/{username}/.matlab/R14 (on Mac)
This is where your "matlab.prf" file is located. Your path may be different depending on how your system is setup.
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 7.0 (R14), rename the directory R14 to R14old. If you also have MATLAB 6.5 (R13) installed on your computer, rename the R13 directory to R13old.
3. Restart MATLAB. A new preferences directory will be created for the MATLAB version that is launched. Please note that the new preferences would be equivalent to the default preferences, including fonts, desktop layouts etc of a new installation of MATLAB.
If this does not address the issue that you hoped it would, it is possible to restore your preferences by deleting the newly created directories (R14 and/or R13) and renaming the R14old and/or R13old directories to their original names (R14 and R13 respectively).
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