Microsoft KB Archive/941020

= You receive occasional Stop errors after you install a driver that manages on-board flash memory on a Windows Vista-based computer =

Article ID: 941020

Article Last Modified on 8/29/2007

-

APPLIES TO


 * Windows Vista Home Basic 64-bit Edition
 * Windows Vista Home Premium 64-bit Edition
 * Windows Vista Business 64-bit Edition
 * Windows Vista Enterprise 64-bit Edition
 * Windows Vista Ultimate 64-bit Edition
 * Windows Vista Starter
 * Windows Vista Home Basic
 * Windows Vista Home Premium
 * Windows Vista Business
 * Windows Vista Enterprise
 * Windows Vista Ultimate

-



SYMPTOMS
On a Windows Vista-based computer, you install a third-party driver that manages on-board flash memory for ReadyDrive. After you install this third-party driver, you occasionally receive a Stop error message that resembles the following:


 * STOP: 0x0000007F

UNEXPECTED_KERNEL_MODE_TRAP



CAUSE
This problem occurs because of an issue in the third-party flash memory driver. This problem only occurs when the system experiences a low-memory condition. The Ecache.sys driver that is included in Windows Vista uses large amounts of memory during startup to cache data. Otherwise, the data would be read directly from the hard disk drive. The cached data improves Windows Vista start times.

The version of Ecache.sys that is included in this hotfix uses memory less aggressively. After you install this hotfix, low-memory conditions are less likely to occur. Therefore, the problem that is described in the &quot;Symptoms&quot; section is also less likely to occur.



Hotfix information
A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites
No prerequisites are required.

Restart requirement
You must restart the computer after you apply this hotfix.

Hotfix replacement information
This hotfix does not replace a previously released hotfix.

File information
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Windows Vista, 64-bit versions


STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section.



MORE INFORMATION
For more information, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates

Additional query words: STOP BugCheck Bug Check BSOD hang freeze NMI bluescreen blue screen

Keywords: kbbug kbfix kbqfe kbexpertiseinter kbhotfixserver kbwinvistapostrtmfix KB941020

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.