In some scenarios your icons will be missing, different or misaligned, this is due to aggressive caching servers or plugins. To solve this you need to exclude the KB files from the caching software.
An example of this issue is like this, you are seeing square boxes beside your articles or Categories
Files to Exclude in the Caching software.
If your using one of these hosting companies you may need to exclude our KB files from their caching software.
Find Plugin Causing This Issue
Disable plugins that could interfere with the icons to see which one is causing this issue.