Arduino library manager issue

[la3pna]

On windows, the library manager is messy, at best.

Close arduino, and go to:
c:\Users\AppData\Local\Roaming\ArduinoXX\

Delete Library_index.json and Library_index.json.temp

Copy and paste this file into the folder: http://downloads.arduino.cc/libraries/library_index.json

[NT7S]

Another way to do it:

Open the Arduino IDE. Select File > Preferences. Click on the link to the preferences.txt location at the bottom of the window. This should open up a file explorer window to the correct location for the library manager json file. Delete any library_index.* files. Close the Arduino IDE. Restart the Arduino IDE and then open the Library Manager (Sketch > Include Library > Manage Libraries...). This should force the Library Manager to grab the latest json file.