Matlab Database gives Java exception

I have used the Matlab Database toolbox for a long time but today it suddenly fails. If I go go Apps>Database Explorer I get the error:

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.toolbox.database.databasePrefs
  at com.mathworks.toolbox.database.gui.DatabaseToolstripTab.<init>(DatabaseToolstripTab.java:242)

...

If for example I write

setdbprefs('DataReturnFormat','structure');

I get the error

Error using javaObject
No class com.mathworks.toolbox.database.databasePrefs can be located on the Java class path

Error in setdbprefs (line 58)
DatabasePrefs = javaObject('com.mathworks.toolbox.database.databasePrefs');

If I write

database(server_name,'','','com.microsoft.sqlserver.jdbc.SQLServerDriver', ...
        ['jdbc:sqlserver://',server_name,':',num2str(port_nr),';database=',database_name,';integratedSecurity=true;']);

I get the error

Error using database (line 309)
Java exception occurred:
java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.toolbox.database.databasePrefs

  at com.mathworks.toolbox.database.databaseConnect.makeDatabaseConnection(databaseConnect.java:140)

I have reinstalled Matlab including the Database toolbox and I have reinstalled Java. I have also downloaded the jdbc driver again in case there was some damage to those files. Still it does not work. I do not know of any changes on my computer since yesterday where everything works.

Thanks for any inputs. Benjamin

Answer 1

[Rahul Goel]

Hi Benjamin,

You can try the following steps to see if it resolves it:

1. Go to the preference directory by executing the following command in the MATLAB command prompt:

>>winopen(prefdir)

2. Look for the file named 'database', change the name of the file to something different ie: 'database_old'

3. Restart MATLAB and check that the file still have the same name ie: 'database_old'.

Hope this helps.

Answer 2

[Benjamin]

Thanks! Worked :)