Can't get 1 password to work after installing extension 4.0.1
I'm trying to use 1Password, but I'm not very smart about computers and can't talk to anyone at Agilebits directly, nor can I get a reasonably timely response to an email request for help so I'm hoping you can help me. I also am not an experienced forum user so I'm not sure how to start, so I'll just state my problem as best I can. I have 1Password 4.0.5 but it didn't have the Secure Notes feature. Something I read suggested that a 3 series extension (which I had) might be the problem. Trying to follow instructions, I uninstalled the 3 series extension and installed extension 4.0.1 which according to Safari, Preferences, Extensions I now have. But when I click the key icon, a little window opens showing an icon of a keyhole and the words "(null) vault." There is no place to enter my password. So now I can't use any feature of 1Password. I know this is probably not an adequate description of my problem, but can anyone help me?