Error message or high CPU utilization when running a WPF-based application
This article helps you resolve the problem where you receive a FileFormatException or ArgumentOutOfRangeException error message in a Windows Presentation Foundation (WPF)-based program when the WPF-based program processes text.
Applies to: Windows Presentation Foundation
Original KB number: 937135
When you run a WPF-based application in the Microsoft .NET Framework 3.0, you may receive a FileFormatException error or an ArgumentOutofRangeException error. The error occurs when the WPF-based application starts to process text. For example, you may receive a FileFormatException error message that resembles the following:
file:///filepath/file_name file does not conform to the expected file format specification.
In this error message, file_name is typically the file name for a font. Additionally, the application consumes up to 100 percent CPU time.
When looking in Task Manager or other tools, PresentationFontCache.exe consumes 50% or more of available processor time.
This issue occurs if video drivers overwrite the data in the font cache that is stored in memory.
To resolve this issue, follow these steps:
Exit all WPF-based applications that are running on the computer.
Stop the Windows Presentation Foundation Font Cache 18.104.22.168 service. To stop the Windows Presentation Foundation Font Cache 22.214.171.124 service, use one of the following methods.
Method 1: Use Microsoft Management Console
- Click Start, click Run, type Services.msc, and then click OK.
- Right-click Windows Presentation Foundation Font Cache 126.96.36.199, and then click Stop.
Method 2: Use the command prompt
- Click Start, click Run, type cmd, and then click OK.
- At the command prompt, type net stop "Windows Presentation Foundation Font Cache 188.8.131.52", and then press ENTER.
Delete the old Fontcache184.108.40.206.dat file.
By default, the Fontcache220.127.116.11.dat file is located in the
%windir%\ServiceProfiles\LocalService\AppData\Localfolder in Windows Vista. By default, the Fontcache18.104.22.168.dat file is located in the
%systemdrive%\Documents and Settings\LocalService\Local Settings\Application Datafolder in Windows XP and in earlier versions of Windows.
Update the video card drivers. To do this, use one of the following methods.
Method 1: Use Windows Update Catalog
To update the video card drivers, check for updates in the Windows Update Catalog. For more information about how to download drivers from the Windows Update Catalog, see How to download updates that include drivers and hotfixes from the Windows Update Catalog.
Method 2: Download and then install the latest video card drivers
To download and install the latest video card drivers, contact the computer or the video hardware manufacturer.
If the video card drivers overwrite the data in the font cache that is stored in memory, the corrupted data may be saved to the hard disk as a data file. Therefore, you may experience the issue that is described in the Symptoms section when another WPF-based application tries to read the corrupted data file.
After you update the video card drivers and after you delete the Fontcache22.214.171.124.dat file, a new font cache data file is created based on the new computer configuration. This new font cache data file is created when the Windows Presentation Foundation Font Cache 126.96.36.199 service is stopped. Typically, the new font cache data file is created when the computer is shut down or restarted.