How to close TCP port 445 which is used for SMB over TCP for Windows XP.
You can easily close port 445 on your computer. To do so follow these instructions:
Start Registry Editor (Regedit.exe).
Locate the following key in the registry:
In the right-hand side of the window find an option called TransportBindName.
Double click that value, and then delete the default value, thus giving it a blank value.
Close the registry editor.
Reboot your computer.
After rebooting open a command prompt and in it type
See that your computer no longer listens to port 445.
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