Zoho is one of the websites the Passpack It! button has issues logging into. This is due to the way Zoho has their login form set up (they use embedded forms on multiple domains).
As a workaround, when you're on the Zoho login page, you can double click your Passpack It! button. This will open a popup window. Click on the tab "copy/paste". You can then click on the icons to copy and paste both your username and password manually into the Zoho Login form.
Here's what the icons stand for.Use this workaround anytime you're not able to use your Passpack It! button on a website's login form.