[TYPO3-english] typo3 6.0.0beta2 upgrade problem

[J. Bakshi]

Hello list,

I am in a phase to upgrade a typo3 sites from 4.7.1 to .0.0beta2

When pressing the upgrade button at install tool; I immediately given the following error

``````````````
Oops, an error occurred!

A cache with identifier "tt_news_cache" has already been registered.

``````````````````

Any clue to fix this. There is no way to proceed further without
fixing this.

Thanks