Can't save to file

Runtime Error: Unable to save file (thumbnail.png) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (thumbnail.png) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/Part3-2.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/ElderAndStaff.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/WhatComesNext.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/FireSpell.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/OuterView.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/Skeleton.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.
Runtime Error: Unable to save file (images/PlanesofExistence.jpg) to cache. Please restart Fantasy Grounds and reset cache on launch screen before rejoining game.


Anyone know what this is about?

Player or GM?
Its either a transient issue that a restart will fix or a permissions issue which may require changing some file/folder permissions in windows.

it is on the player side.

Side question: The player in question did not have a laptop so I let him use my spare. I created a seperate user profile and had him log in to it. That should not be an issue, right?