So you did clear out the entire C:\Program Files\Electronic Arts\EA Downloader\cache folder before redownloading, and you have done everything that the guy on totalbf2 forums suggested - nasty one then.
A friend of mine mentioned a problem along the same lines but is away for a couple of weeks, i will try and contact him to see if he resolved the issue and how.
Let us know if EA support resolve the problem - i bet it's frustrating when one of their suggestions is to restart the computer

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