Blue icons after ReadyBoost

These blue icons appeared on a lot of things once i turned on ReadyBoost on a 1 GB stick. Is that normal?

You shouldn't be using a 1GB stick alone for Readyboost. You can use it if you have atleast 3GB on other sticks being used by Readyboost but you should always use between 1 and 1.5 times your current ram.

EDIT: Apparently those icons are created by Norton, not Readyboost. They're green checks when the files have been backed up completely and they're blue arrows when the files are in the process of being backed up.

Source: http://www.winhelponline.com/blog/g...rlay-displayed-for-files-in-windows-explorer/

But I have backup disabled on norton 360.