Hello!

Try this:

Open up iTunes
In iTunes fo to File>Add to Library

Browse to the file in question

When you have found it select in and click the select/add(dependent on language version) button.Now in the pop up script window that appears click ok.

Now in your music library inside iTunes look up you recently added file and double click it and it should start playing if it has the proper mp3 extension and are in mp3 format.

If it did not work then read my previous response in this question Here!

If not even that helped you then I would start to suspect something serious like directory damage.Use Disk First Aid to check for any errors on your HD and also use Tech Tool Lite to delete the desktop file and zap PRAM.If it found errors then you will need a third party disk utility like DiskWarrior to repair the HD.

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<img src="http://www.jordysworld.de/emoticons/blob16.gif">Sincerely Joakim Agren!