A hotfix is already available for download from Microsoft Support

Nov 8, 2011 11:21 GMT  ·  By

Windows 7 users have come across an issue related to DirectX and Graphics Device Interface (GDI), in which black lines are displayed in the windows of some of their applications.

Microsoft confirmed the problem, and is already providing customers with a hotfix designed to resolve this particular glitch.

The software giant notes that only application windows that are displayed through a combination of DirectX and GDI are impacted by this issue.

The glitch can be experienced by those running Windows 7 RTM and Service Pack 1, as well as Windows Server 2008 R2 and SP1.

“If you change the size of the application window, the black lines may disappear temporarily,” the software giant said. “This issue occurs when the application calls certain functions, such as the DwmGetCompositionTimingInfo function.”

Microsoft has already identified the source of the problem, and offered the following details:

“This issue occurs because DirectX incorrectly takes Device Bitmaps mode code path when Vista Blt mode is enabled. When certain functions are called, incorrect flags are returned to the caller. Therefore, DirectX does not detect that Vista Blt mode is enabled,” the company said.

KB 2578764 deals with this specific problem, and also offers a link to the hotfix that Microsoft Support made available.

The fix should only be deployed by those users that are impacted by the issue described above.

Device Bitmaps mode is new to Windows 7 and Windows Server 2008 R2, with the software giant introducing it in order to boost interoperability between DirectX and GDI.

“Device Bitmaps mode was introduced because Vista Blt mode, which is used in Windows Vista and in Windows Server 2008, may cause high memory usage,” Microsoft added.

“When an application uses DirectX and GDI to display the application window in Windows 7 or in Windows Server 2008 R2, Device Bitmaps mode is enabled. However, if the application calls certain functions (such as the DwmGetCompositionTimingInfo function), the interoperation mode is changed to Vista Blt mode.”

Windows 7 SP1 RTM and Windows Server 2008 R2 SP1 RTM are available for download here.