Browsers ships with certificates from well-known commercial CAs. If your web servers use certificates signed by your own CA, your CA certificate must be exported to every browser on every client system that will be connecting to an SSL-enabled web server.

To import a new CA into Firefox 1.5 

1. Launch Firefox and choose Preferences from the Edit menu.
2. Click the Advanced button.
3. Select the Security pane.
4. Click the View Certificates button.
5. Click the Authorities tab.
6. Click the Import button at the bottom of the screen.
7. Navigate to the CA certificate and import it.
8. Click the "Trust this CA to identify web sites." checkbox
9. Click the "Trust this CA to identify email users." checkbox
10. Click the "Trust this CA to identify software developers." checkbox
11. Click the "OK" button

To import a new CA into Firefox 3.0

1. Launch Firefox and choose Preferences from the Edit menu.
2. Click the Advanced button.
3. Select the Encryption pane.
4. Click the View Certificates button.
5. Click the Authorities tab.
6. Click the Import button at the bottom of the screen.
7. Navigate to the CA certificate and import it.
8. Click the "Trust this CA to identify web sites." checkbox
9. Click the "Trust this CA to identify email users." checkbox
10. Click the "Trust this CA to identify software developers." checkbox
11. Click the "OK" button

To import a new CA into Internet Explorer 6

1. Obtain the certificate file from your administrator and save it locally
2. Right click the certificate and select Install Certificate - Next
3. Choose Place all certificates in the following store - Browse
4. Highlight Show Physical Stores
5. Expand "Trusted Root Certification Authorities"
6. Highlight Local Computer - OK - Next - Finish
7. Press OK when you are notified the import is successful
8. Open Internet Explorer. You should not receive the security alert when accessing the https enabled web server. This means the CA is now trusted.

To import a new CA into Internet Explorer 7

1. Obtain the certificate file from your administrator and save it locally
2. Right click the certificate and select Install Certificate - Next
3. Choose the "Place all certificates in the following store" radion button,  - Browse
4. Click the "Trusted Root Certification Authorities" list item, - OK
5. "Certificate Store" - Next - Finish
6. Press OK when you are notified the import is successful, and press OK again to finish the process.
7. Open Internet Explorer. You should not receive the security alert when accessing the https enabled web server. This means the CA is now trusted.

In this WWU computer helpdesk page, there are some screenshots for importing the certificate into different browsers.