This article was previously published under Q258437
This article has been archived. It is offered "as is" and will no longer be updated.
In Windows NT 4.0 Service Pack 6 (SP6) and in Windows NT 4.0 Service Pack 6a (SP6a), the GetEffectiveRightsFromAcl function is broken. For a given discretionary access-control list (DACL), GetEffectiveRightsFromAcl returns the same access mask for all users even though different users may have different access rights. The function works correctly in Windows NT 4.0 Service Pack 5 (SP5).
Without GetEffectiveRightsFromAcl, there is not a good way to enumerate a user's access rights for a particular object. However, if you just want to determine whether a user has access to an object and you have the user's token, you can use the AccessCheck function.
A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem.
To resolve this problem immediately, download the fix by clicking the download link later in this article or contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:
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.
The following files are available for download from the MicrosoftDownload Center: Windows NT 4.0:
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 tool in Control Panel.
Date Time Version Size File name ------------------------------------------------------ 25-Apr-2000 19:00 4.0.1381.7048 84,240 Ntmarta.dll
Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.
For more information about how to call AccessCheck, click the following article number to view the article in the Microsoft Knowledge Base:
171273 How to program a secure server on Microsoft Windows NT