How to upgrade magento 1.4 1.1 to 1.7.0.2
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I have a magento site in `1.4.1.1`.

Now i want to uprgade the site to `magento 1.7.0.2`.

I already did the following steps:

    1.system->magento connet->magento connect manager
    2.Then pressed tCheck for Upgrades button

But the there have no list for `Manage Existing Extensions.`

So how can i do the upgarde using magento connect manager?

How can i upgarde the magento site ?




