What Is the SFCACHE File Extension?

by Jane Buchanan

If you have recently plugged a Universal Serial Bus flash drive into your computer, you might have noticed a large file with an SFCACHE file extension on it. This file type is generated by a Windows technology called ReadyBoost, which makes use of a standard USB drive in an unusual way.


ReadyBoost is a technology which allows your Windows computer to use a standard USB flash drive as a memory cache. Your computer will then be able to use that cache to store frequently-accessed data, which in turn helps make your system faster. The ReadyBoost technology is available in Windows Vista, 7 and 8.

Enabling ReadyBoost

To enable ReadyBoost, simply insert a formatted USB flash drive into a USB port on your computer and select "Tap to choose what happens with removable drives." Selecting "Speed up my computer" on the next screen will then bring up a dialog box which will allow you to enable ReadyBoost on your machine.

About the Author

Jane Buchanan earned a master's degree in computer science from the University of Virginia in 1991. Since then, she has worked as a journalist and copy editor for the "Daily Press" and the "Arlington Connection."

Photo Credits

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