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Hello, I am desperate because I can not understand if I can do what I thought ..

I installed WP 3.6 with multisite option and what I want to achieve is the following situation ..

.. I wish I could insert the contents in the main site and to assign them to one or more of the sites connected to the network.

alternatively could fit even the opposite solution where all the contents of the various sites are “recovered” even from the main site.

thanks
Elisa