Try this To disconnect from the network
Open Network Connections.
Right-click the connection you want to disconnect, and then do one of the following:
If it is a dial-up, VPN, or incoming connection, click Disconnect.
If it is a local area network connection, click Disable.
To open Network Connections, click Start, click Control Panel, and then double-click Network Connections.
If you disconnect a local area connection, it disables the network adapter driver until the connection is reactivated.
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