If your Vista Firewall does not start automatically at startup, then here are a few trouble-shooting steps you may try:
First scan your machine for malware using a good anti-virus and an anti-spy. If you have installed a 3rd party firewall or a Security Suite, then that could also be the cause for the problem.
Next, type services.msc in Vista's Start Menu Search Bar and hit Enter to open up Services. here ensure that the Windows Firewall Service is started and set on Automatic. Also ensure that the Remote Procedure Call Service is started and set on Automatic.
Now you also have to ensure that the Windows Firewall Authorization Driver (mdsdrv.sys) is running properly.
To do so, type devmgmt.msc in search bar and hit enter to open Device Manager. In views tab check on Show Hidden Devices and also show Devices By Connection.
Locate Windows Firewall Authorization Driver in the list and double click on it to open its Properties box. Click on Driver tab and ensure that the process is started and startup type is Demand. Click OK.
Reboot. Hopefully your Vista Firewall should be working OK now.
If it does not help then run Group Policy Result Tool to check if there is a firewall policy blocking it. Type gpresult -z in Search Bar, rt click on the result and run it as Administrator.
Check under Resultant Set Of Policies For Computer, esp under Security Options.
Incidentally, drifting a bit, should you need to access following panels easily, you can type the following run commands in Vista's Start Menu Search Bar and hit Enter
Firewall Settings : FirewallSettings
Firewall Control Panel : FirewallControlPanel
Windows Firewall with Advanced Security : wf.msc
