Probably you have noticed that Windows 7 will pop up annoying messages when not being able to reconnect network drives on boot. If for some reason they have to be unavailable you can disable pop up message using following registry change:
Hive: HKEY _CURRENT_USER
Key: Network
Value Name: RestoreDiskChecked
DWORD Value: 0 = disabled, 1 = enabled
você pode ter que criar o Dword RestoreDiskChecked se ele não estiver presente.