Having windows 7 automatically update is fine and all but by default it will reboot the computer if needed. That can be a problem. So to prevent that, take the following text and save it as ‘automaticrebootoff.reg’ in notepad and then double click on it to import it into the registry. This turns the automatic reboot off for good.
### START (do not copy this line) ####
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate]
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU]
“NoAutoRebootWithLoggedOnUsers”=dword:00000001
### END (do not copy this line) ####