Large Writes to Removable Media May Result in Data Loss

ID: Q239694

The information in this article applies to:

Microsoft Windows 98
Microsoft Windows 98 Second Edition

SYMPTOMS

When a program attempts a large write to an ATAPI magneto-optical disk or an ATAPI Zip drive, the write process may not be completed and no error message may be returned to the program. This problem can potentially occur in programs that submit a single write request that is larger than approximately seven megabytes (MB).

You can identify this problem by using the File Compare (Fc.exe) utility to compare the source file with the destination file located on the removable media.

This problem does not occur with utility programs such as copying or using Windows Explorer to copy files, because these tools use multiple small buffers to copy a file.

CAUSE

This problem occurs because the input/output (IO) subsystem times out requests that take longer than 7.5 seconds and the large write process does not have enough time to finish.

RESOLUTION

A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems 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 on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

The English version of this fix should have the following file attributes or later:


   Date      Time    Version    Size    File name     Platform
   -----------------------------------------------------------------
   08/03/99  03:02p             24,430  Esdi_506.pdr  Windows 98
   08/12/99  09:03p             24,430  Esdi_506.pdr  Windows 98 
                                                      Second Edition

WORKAROUND

To work around this problem, use a smaller buffer when writing to removable media when you use WriteFile to write data to a file.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article.

MORE INFORMATION

The Max Transfer Length setting for removable media has been decreased so that Windows breaks up large writes into smaller requests that do not exceed 7.5 seconds.

Additional query words:

Keywords : kbhw diskmem win98 win98se
Version : WINDOWS:98 Second Edition
Platform : WINDOWS
Issue type : kbprb