The problem was caused by the Browser setting to check for server certificate revocation when using IE or Firefox.

Chrome does not check this.

In IE the setting can be removed as follows

1. Open Internet Explorer.
2. From the Tools menu, select the menu item Internet Options and click on the Advanced tab.
3. Scroll down to the Security section, uncheck the option Check for server certificate revocation.

In Firefox:

1. Open Firefox

2. Click on the "Settings" icon.

3. Select the "Advanced" tab on the "Options" window.

4. Select the "Encryption" tab.

5. Click on the "Validation" button.

6. Remove the check mark from the box on the "Certificate Validation" window and click "OK."