I upgraded to 1Password4 from the Apple App Store after the beta expired. Clicked the 'I am an existing user box'. Selected Dropbox sync. When prompted to select Dropbox folder, selected it from Finder, then selected 1Password.agilekeychain. 'Welcome to Password4!' screen appears, saying it has found my data in Dropbox and prompts for Master Password. Here's the problem: when I enter the Master Password, the lock icon moves to the open position, then the process just hangs. 1Password does not open. I was able to create a secondary vault and point to the 1Password.agliekeychain file, thereby creating a vault called 1Password, but the Primary Vault remains empty. I have followed the Start Over instructions in the database twice and get the same result each time. Fortunately, 1Password remains usable. When the program opens, it asks for the password for the Primary Vault, which opens empty. I then switch to the secondary 1Password vault. This is not a fatal problem, but it's quite irritating. Any help much appreciated.