FIX: GetDiskFreeSpaceEx May Return the Wrong Values (314417)

RESOLUTION

WORKAROUND

You might avoid this problem if you do one of the following:

Wait at least four to five seconds before you issue a second call to the GetDiskFreeSpaceEx API.

-or-
Use GetDiskFreeSpace instead, which is the older version of the API.

NOTE: The GetDiskFreeSpace API can only report disk sizes up to 2 gigabytes (GB).

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
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, 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:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

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 English version of this fix has the file attributes (or later) 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    Platform
   -----------------------------------------------------------------
   11-Jan-2002   13:13   4.90.3007   161,849   Vredir.vxd   i386

MORE INFORMATION

To improve performance in Windows Millennium Edition, a caching mechanism was implemented to hold disk attributes that are returned from remote computers. This cache holds the values for three seconds before it must be refreshed.

A problem in the mechanism makes it cache the wrong values. Later calls to the GetDiskFreeSpaceEx API derive their values from this cache. Therefore, the later calls return the wrong values.