How to Install the InterceptSuite CA Certificate on Windows

To intercept HTTPS traffic, your operating system must trust the InterceptSuite Certificate Authority (CA). This guide walks you through exporting the certificate from InterceptSuite and installing it as a trusted root CA on Windows.

For a video guide, watch: InterceptSuite MITM Setup: Install CA Certificate on Windows

The Fast Way: Install Certificate Button (2.1.0 and Later)

InterceptSuite 2.1.0 can install its own CA certificate, so for this computer you can skip the manual steps below.

1. Open Proxy > Settings and find Certificate Management.
2. Click Install Certificate.
3. Click Yes on the Windows permission (UAC) prompt.

It adds the certificate to Local Machine > Trusted Root Certification Authorities for all users, replaces an older InterceptSuite certificate if there is one, and checks afterwards that it is really in the store. InterceptSuite itself does not run as administrator; only that one step asks for permission. See Proxy Settings for details.

Use the manual steps below when you need the certificate on another computer or device, in an application with its own store such as Firefox, or if the button reports a problem.

Step 1 - Export the CA Certificate from InterceptSuite

Before installing the certificate, you need to export it from the application.

1. Open InterceptSuite and navigate to the Proxy tab
2. Click the Settings sub-tab within the Proxy section
3. Scroll to the Certificate Management section
4. Click Export Certificate
5. When prompted for format, select DER
6. Choose your preferred save location (e.g. your Desktop)
7. Click Save - you should now have a .der file

Step 2 - Install the Certificate

Windows lets you install a certificate directly by double-clicking the file - no MMC required.

1. Double-click the .der file you exported

2. Windows will open the Certificate dialog showing the certificate details

3. Click Install Certificate…

4. Choose the store location:

   • Current User - installs only for your Windows account
   • Local Machine - installs for all users on this PC (requires admin)

   Select whichever fits your needs and click Next

5. Select Place all certificates in the following store and click Browse…

6. In the list, select Trusted Root Certification Authorities and click OK

7. Click Next, then Finish

8. Click OK on the success dialog

If you chose Local Machine, Windows will prompt for administrator confirmation - click Yes.

Step 3 - Verify the Installation

1. Press Win + R, type certmgr.msc, and press Enter (for Current User) - or certlm.msc for Local Machine
2. Expand Trusted Root Certification Authorities → Certificates
3. Look for InterceptSuite in the list
4. Double-click it to confirm the certificate details match

Step 4 - Configure Your Browser or Application

Now that the system trusts the CA, configure your application to use InterceptSuite as a proxy:

• Proxy host: 127.0.0.1
• Proxy port: 4444 (or whichever port you configured)

Most browsers on Windows (Chrome, Edge) use the system certificate store automatically. Firefox uses its own store - see the Firefox-specific section below.

Built-in Traffic Redirect (Windows, 2.1.0 and Later)

On Windows you no longer need a separate tool to route an application through InterceptSuite. Open Proxy > Redirect, add a rule for the program with Action: Proxy, and click Start Redirect. It works for TCP and UDP. See Traffic Redirect.

ProxyBridge - Recommended Proxy Client

ProxyBridge is a free, open-source proxy client built by the InterceptSuite team. It makes routing any application through InterceptSuite on Windows effortless -no manual proxy settings needed per app.

• Forces any process to use a SOCKS5/HTTP proxy regardless of its own proxy settings
• Works with apps that don't natively support proxy configuration
• One-click setup with InterceptSuite
• Available on GitHub

Firefox on Windows

Firefox maintains its own certificate store and does not use the Windows system store by default.

1. Open Firefox and go to Settings → Privacy & Security
2. Scroll to Certificates and click View Certificates…
3. Go to the Authorities tab and click Import…
4. Select your .der file and click Open
5. Check Trust this CA to identify websites and click OK

Troubleshooting

Certificate warnings still appear - Make sure you selected Trusted Root Certification Authorities as the store during installation. Restart your browser after importing.

Double-click doesn't open the certificate dialog - Right-click the .der file and choose Open With → Crypto Shell Extensions.

Local Machine install requires admin - Right-click the .der file and choose Run as administrator, or use the Current User option which doesn't need admin rights.

Once the certificate is trusted, start intercepting TLS traffic with InterceptSuite - 7-day free trial, no credit card required.