Tag: pac file

Applies to: CyBlock · Connecting browsers to your CyBlock web filter — manual settings for testing, PAC file via Group Policy for production.

CyBlock is a web filter that businesses use to control and monitor employee web access. To have a browser send its traffic through CyBlock, you point the browser at your CyBlock server using its connection settings. There are two ways to do this: for production, push CyBlock’s PAC file to all browsers using Group Policy (GPO) so every machine is configured automatically and stays consistent; for quick testing on a single machine, enter the connection settings manually in the browser.

Before you begin

You’ll need your CyBlock connection settings:

• The server address and port for your CyBlock filter
• Your PAC file URL (for PAC-based setup) — see Finding your PAC file URL below

Where to find your connection settings: These are specific to your deployment. Find the server address and port in the product under Settings → Proxy. If you’re on the CyBlock Cloud service, use the connection details Wavecrest provided when your account was set up. If you can’t locate them, contact us at 321-953-5351 or support@wavecrest.net.

Finding your PAC file URL

Your PAC file URL is available in CyBlock at:

Settings → Proxy → PAC File

Use this URL wherever a PAC or automatic-configuration URL is required below.

Which method should I use?

• Production → push the PAC file via Group Policy. It’s centrally managed, consistent across all machines, and updates everywhere when the PAC file changes.
• Testing / a single machine → enter the connection settings manually in the browser.

Manual setup (for testing)

Google Chrome, Microsoft Edge, and Internet Explorer (Windows connection settings)

Chrome, Edge, and Internet Explorer all use the Windows system connection settings, so configuring them once covers all three. (Chrome’s and Edge’s own buttons simply open these Windows settings.)

Windows 10 / 11:

1. Open Settings → Network & Internet → Proxy.
2. To connect directly: under Manual proxy setup, turn on Use a proxy server and click Set up. Enter your CyBlock server address and port, then click Save.
3. To use the PAC file instead: under Automatic proxy setup, turn on Use setup script, enter your PAC file URL, then click Save.

Classic dialog (any Windows version):

1. Press Win + R, type inetcpl.cpl, and press Enter to open Internet Options.
2. On the Connections tab, click LAN settings.
3. To connect directly: check Use a proxy server for your LAN, enter your CyBlock server address and port, and clear the other checkboxes.
4. For the PAC file: check Use automatic configuration script and enter your PAC file URL in the Address field.
5. Click OK, then OK again.

Mozilla Firefox

Firefox keeps its own connection settings, separate from Windows.

1. Click the menu button (☰) and choose Settings.
2. In the General panel, scroll down to Network Settings and click Settings….
3. To connect directly: select Manual proxy configuration, enter your CyBlock server address in the HTTP Proxy field, enter your port, and check Also use this proxy for HTTPS.
4. For the PAC file: select Automatic proxy configuration URL and enter your PAC file URL.
5. Click OK.

To have Firefox follow the Windows setting instead, choose Use system proxy settings.

Pushing the PAC file via Group Policy (for production)

Use Group Policy to deploy the PAC file to all managed browsers automatically. The correct method depends on the browser.

Google Chrome and Microsoft Edge (ADMX policies)

1. Import the Chrome and/or Edge ADMX templates into your domain Central Store (if not already present).
2. In Group Policy Management, edit the GPO that targets your users or computers.
3. Go to Computer Configuration → Policies → Administrative Templates → Google → Google Chrome → Proxy server (for Edge: Microsoft Edge → Proxy server).
4. Enable Choose how to specify proxy server settings and set it to Use a .pac proxy script.
5. Enable URL to a proxy .pac file and enter your PAC file URL.
6. Apply the GPO. Clients pick it up on the next policy refresh, or immediately with gpupdate /force.

Windows connection settings / Internet Explorer (Group Policy Preferences)

For browsers that rely on the Windows system connection settings (Internet Explorer, and Chrome/Edge where their own ADMX policies aren’t used):

1. In Group Policy Management, edit your GPO.
2. Go to User Configuration → Preferences → Control Panel Settings → Internet Settings and create a new item for your Windows/IE version.
3. Enable the Use automatic configuration script option and enter your PAC file URL. Press F5 so the setting applies (it turns green).
4. Apply the GPO.

The exact controls vary by Windows version; if the Internet Settings preference doesn’t expose the auto-config field on your build, push the PAC URL by setting the AutoConfigURL value under HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings with a Registry preference instead.

Note on older documentation: Earlier guides configured this through Internet Explorer Maintenance (User Configuration → Windows Settings → Internet Explorer Maintenance → Automatic Browser Configuration). That method no longer applies — Microsoft removed Internet Explorer Maintenance for managing Windows 8 and later, and Internet Explorer was retired in June 2022. Use the ADMX or Internet Settings methods above.