I recently bought a laptop with Windows 7 Home Premium and set this up with another computer running Windows Vista Home Premium. This worked fine. Then I went away for a month and whilst I was away upgraded my laptop from Windows 7 Home Premium to Windows 7 Professional. Now I cannot seem to access the other computer files or printer and it can no longer access my laptop. I have tried pinging the ip address and that works fine but if I ping by hostname I get the error message "cannot find host". Both computer are on the same workgroup and both appear in the network window but if I click on one I get "error code: 0x80070035. The network path was not found"