I've been having this issue every day for 2 or 3 weeks. I open Chrome, and the 1Password icon has a red exclamation point on it. I have restarted the Helper repeatedly, and it doesn't help. Restarting the 1Password app doesn't help. Sometimes (but not always) restarting my iMac helps. I've deleted and re-installed the browser extension a dozen times, but that doesn't help either.
If I type in the password in the browser prompt, I get a big red error message on the left navigation bar of the extension, but it works.
When Chrome is having this issue, the browser extension for Safari works fine.
I'm using an iMac with OSX 10.7.5 installed, and I have version 3.8.20 (build 31499) of 1Password from Agilebits with version 126.96.36.199 of the Chrome browser extension installed.