Sometimes it is necessary to install the community channel manually.
F.e. in EE. 18.104.22.168 I got the following error massage in the Magento-Connect-Manager shell when I tried to install a package via “Direct package file upload”:
CONNECT ERROR: The 'community' channel is not installed. Please use the MAGE shell script to install the 'community' channel.
What I had to do is to run the following commands on shell:
$> # go to magento root folder $> cd /pathtomageroot $> # make mage shell script executable $> chmod 777 mage $> # run the setup $> ./mage mage-setup
After that you should see an message like this:
Running initial setup... Success Success Successfully added: http://connect20.magentocommerce.com/community
Thats it! Now you should be able to install community modules over the Connect manager.