You might have accidentally disabled Unifeed or it was disabled by other plugin due to a plugin conflict.
Open 'chrome://extensions' tab in Chrome, scroll down to Unifeed and make sure 'Enabled' checkbox is turned on.
Since Unifeed relies on social network websites, please make sure you can actually browse posts on those websites.
If you're sure something is wrong, please send us a mail and include the following:
1. An explanation / screenshot of the problem you experience.
2. A debug info file which can be generated from Unifeed Settings page.
We will be happy to assist and smash that nasty bug!