'Agent not connected' error with Firefox 6/7 on Leopard

The new extension that we use for Firefox 6 or 7 is not supported on Leopard. We did however released 1Password 3.5.15 with support for Firefox 6/7 on Leopard, but you need to use 1Password 3.5.15 to install the Firefox extension. Here's how to get set up:

  1. Be sure you're running the version of 1Password you need for Leopard. You can get it from our Legacy Versions page
  2. Uninstall the new extension for Firefox - Open Firefox and go to the Tools Menu > Add-ons > Extension
  3. Select the 1Password extension and press "remove" to send it packing
  4. Install the proper extension - Open 1Password and go to the 1Password Menu > Preferences > Browsers to install the Firefox 7 extension.