I got the similar error when u upgrading from 1.1.6 to 1.1.7 with connection manager.
When I click for âUpdateâ I was redirected to Magento installation wizard (why actually, it isnât a new installation, but just an update ?!). In the first installation step I clicked on âStart the download process buttonâ. Then I got the message âIgnoring installed package magento-core/Mage_All_Latest. Nothing to installâ . When I click the âContinue Magento installationâ button , the installation procedure send me back to the first step with the âStart the download process button. So Iâm hanging between two pages (see attachment). The worst is that when you try to open my site or admin console you will be redirected to magento wizard. As result - the site is unavailable !
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