There can be several causes that will prevent the Windows Firewall from starting and I will attempt to cover them in this series of five blog posts. In this first post, I will cover Windows XP and Windows Vista / Windows 7 separately as they are two different services. Last I will cover one issue with OneCare. Note: Specifics on Windows Vista and Windows 7will come in a later blog post.
In Windows XP, the firewall service is named "Windows Firewall/Internet Connection Sharing (ICS)", or SharedAccess service.
Typical errors seen as either popups or within event logs when the service fails to start are:
Problems starting the Firewall Service in Windows XP are most commonly related to an issue with the Shared Access registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess
The quickest resolution is generally to rebuild the key. Instructions for doing this are in the following article, along with a FIXIT link:
You cannot start the Windows Firewall service in Windows XP SP2
Other things you will want to check are:
The above 3 items cover the vast majority of the issues with starting the Firewall in Windows XP.
In Windows Vista and later, the firewall service is "Windows Firewall" (MPSSVC); it combines both Firewall and IPsec functionality.
The first thing to check is that the Base Filtering engine (BFE) is running. There are a number of services dependent on the BFE service (including the Windows Firewall) that may also fail to start:
In my experience most of the issues starting these services are related to permissions.
Typical errors seen in relation to starting this service are:
What to look for (specific details will be shared in a future blog post):
Lastly, I am including information about one issue that may be seen with the Windows OneCare Firewall Service. The following messages may be seen:
The Windows OneCare Firewall Service Could not Start
Urgent - Turn on Firewall
You will see this error in the Windows OneCare interface, with a red status action item asking you to enable the firewall. The action listed does not enable the firewall, however.
This issue is also very specific because the firewall settings in Windows OneCare are grayed out and cannot be modified.
To resolve this issue:
Use the steps below to ensure that the PATH environment variable contains the following path:
%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\system32\WBEM
If this does not resolve the issue, try the following step:
If this does not resolve the issue, or if the problem does not match the description, please follow the steps in KB article 910659.
This wraps up my overview of how to troubleshoot issues starting the Windows Firewall Service. I will have some future blog posts with more specific details on the Windows Vista/Windows 7 steps.
- David Pracht