“An unknown error occured.” It can occur -
With Better WP security plugin
This plugin is known to cause problems in displaying available updates and also while applying available updates. To fix this -
1. Go to Security -> System Tweaks
2. Under the Dashboard Tweaks section, uncheck all 3 options “Hide Theme Update Notifications”, “Hide Plugin Update Notifications”, “Hide Core Update Notifications” and click Save Changes.
With W3 cache
If you don’t see your updates properly try deactivating and activating the W3 cache plugin
If you get this error and you are not using any of the plugins above. This error occurs when the plugins / themes are already updated but InfiniteWP panel shows that they still need to be updated. It can be due to WordPress cache and this can be solved by going to the update page of that particular WP site or it should resolve itself in another 4 hrs max when WP refreshes its update section.
As of version 1.1.2, you can clear the cache and Reload data to fix this issue.