Where Customization Begins 

  • Presentation Font Cache

 #25113  by Neuropass
 21 Jan 2013, 05:08
What is Presentation Font Cache?

The Presentation Font Cache is part of the Windows Presentation Foundation (WPF) feature, which allows programmers to develop graphically richer applications. It’s part of the .NET Framework (3.0, 3.5, 3.5 SP1 and 4.0), which, in turn, is part of Windows Vista (3.0) and Windows 7 (3.5).

Some of your installed applications may require WPF and make use of the Presentation Font Cache. This service loads font glyph information into memory and helps share these fonts with all of the installed WPF applications. As such, applications that use the WPF framework start a bit quicker, and font pickers (such as this one) might see a slight performance increase.


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By default, this service is set to manual, so it won’t launch automatically and cause performance improvements (in non-WPF applications) or any problems. However, once you use a WPF program, this service will start and—in some cases—set to start automatically when Windows launches!

Why is it burning my CPU?

The Presentation Font Cache loads all fonts into its font cache (which is stored on your hard disk, but more on that later). However, at some point, this cache may become corrupted and unreadable due to a specific font. Then, the Presentation Font Cache will start to become unresponsive and get caught in a “I try to launch, but I’m stuck, so I will try it again” loop. That’s what causes the incredibly high CPU usage, and what may even result in a sudden shutdown due to overheating. Luckily, there are a few solutions to this problem!

Solution #1: Delete the font cache file


The font cache is located under the following folder: %windir%\ServiceProfiles\LocalService\AppData\Local. Simply hold down the WIN key on your keyboard and press “R”. Then, enter the path above and click “OK”. Delete all the “FontCache…dat” files you find, such as “FontCache-System.dat” or “FontCache3.0.0.0.dat”.


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This will cause the WPF font cache to rebuild itself. However, if the problem persists, you might need to shut down the WPF font cache permanently.

Solution #2: Shutting down the WPF font cache

If all else fails, you have no choice but to disable the font cache. This may cause a slight slowdown when loading applications that heavily rely on fonts or offer a font picker (which loads hundreds or even thousands of your installed fonts). But, it’s a lot less painful then working under 50% CPU stress and hearing a fan working on overdrive. So how do you get rid of WPF font cache? It’s simple—go to “Control Panel”, and click on “System and Security”, “Administrative Tools” and “Services”. Scroll all of the way down until you see “Windows Presentation Foundation Font Cache”. Double-click on this entry, and select “Disabled” from the “Startup type” list.

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That’s it! Click on “OK”, and reboot your system. You may encounter some slight delays in your WPF applications, but at least your PC will be running at full speed again.