For many grid-based web services, you need to have your certificate loaded into your browser.  To do this, go back to the CA and download your certificate in "PKCS12" format.  If you generated your certificate separately (GPN users did not), a PKCS12 certificate can be generated with the following openssl command:

openssl pkcs12 -export -inkey userkey.pem -in usercert.pem -out my_cert.p12 -name "My certificate"

Save the file as "my_cert.p12" on your desktop (or copy it to your desktop) so it is easy to find.  Each browser has its own mechanism for importing user certificates.  Here are guidelines for several popular browsers:

Instructions to load certificates into some common browsers are given below. They have been adapted from the LCG documentation.  Version numbers are given for guidance only.

Firefox (version 1.0.x)

1. Start Firefox.
2. Go to the Edit menu and select "Preferences -> Advanced".
3. In the 'Certificates' find 'Manage certificates' button and click on it. This will open a dialogue box.
4. Click on the tab 'Your certificates' find the 'Import' button and click on it.
5. Give the path to the file my_cert.p12.

1. Start Firefox.
2. Go to the Edit menu and select "Preferences" (the preferences may be under the "Firefox" menu or the "Tools" menu, depending on what OS you use).
3. Select the "Advanced" tab, and click on "Security".
4. Click on the "View Certificates" button.  This will open up the certificate manager. 
   
5. Click on the "Your Certificates" tab, and then the "Import" button. 
   
6. Import the certificate file my_cert.p12.  Firefox will ask you for your certificate's passphrase.
   

Mozilla (version 1.x) or Netscape (version 7.x)

1. Start Netscape.
2. Go to the Communicator menu and select "Tools -> Security Info".
3. Click on "Certificates/yours'' section. This will open a dialogue box.
4. Click on "Import a Certificate'' button. You will be asked a new password to protect your Netscape Certificate Database (remember this password as you will need it to import other certificates). You will be able to choose your PKCS12 (.p12) file from a standard file selection dialogue.

Internet Explorer (version 6.x)

1. Start Internet Explorer
2. Go to the Tools menu and select "Internet Options".
3. Choose the Content tab and click on Certificates which will open a dialogue box.
4. Click on Import to start the Import wizard and follow the instructions. The certificate should go into the "Personal'' certificate store and you should also select "high security" to prevent Internet Explorer saving your pass phrase.

Opera (version 7.x)

Konqueror (version 3.x)