So for starters, both have windows 7? Since your talking about setting up a home group for both i assume this to be true. Have you set up sharing on both computers? It requires some minor tweaking to set up a home group. You need to specify when folders you would like placed in the home group. Question, are the user accounts on each computer the same? if not try this (refer to screen shot) Try setting it to manage the user accounts individually for the connection to the computer home group
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