Possible Database File Damage When Data Is Appended

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Database programs running in Windows 95 OEM Service Release 2 (OSR2) or 2.1 (OSR 2.1) over a Microsoft network may damage the database.
When a program uses the GetFileSize() API to get the size of an existing file on a Microsoft networking server (such as a Windows NT-based server), the Client for Microsoft Networks may not return the correct file size. When the program then attempts to write additional information to the end of the file, it may overwrite existing data instead.

This problem has been observed only with the version of the Client for Microsoft Networks (Vredir.vxd) included with OSR2 (version 4.00.1111) and later.
This issue is resolved by the following updated file for Windows 95 OSR2:
Vredir.vxd version 4.00.1116 (dated 9/11/97) and later
To install this update, follow these steps:
  1. Download the following file from the Microsoft Download Center:
  2. Double-click the Vredrupd.exe file that you downloaded in step 1.
  3. Follow the instructions on the screen.
For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base:
119591 How to Obtain Microsoft Support Files from Online Services
Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

The following files are installed by Vrdrupd.exe:
   File name     Version    Date/Time        Size     Destination folder   ---------------------------------------------------------------------   Vredir.vxd    4.00.1116  9/11/97 11:16a   156,773  Windows\System   Vnetsup.vxd   4.00.1112  5/30/97 11:12a    17,595  Windows\System				
More information
For additional information about issues resolved by updates to this component, please see the following articles in the Microsoft Knowledge Base:
172594 Cannot Connect to Server with 15 Characters and Period in Name
165402 Windows 95 Update to Encrypt Passwords in Memory
161100 File May Be Truncated When Copied to a Full Network Drive
157114 "Access Denied" Attempting to Run File on LM/X Server
152186 Possible Network Data Corruption If Locking Not Used
148367 Possible Network File Corruption with Redirector Caching
142803 Hang or Locking Error Accessing Database Files Over Network
140558 Deleting Files on Samba Servers May Delete Local Files Instead
138249 Updated Vredir.vxd Corrects Errors Running Files on LMX
160807 Cannot Connect to Windows NT Server with Many Shares
150215 Disabling Automatic Network Shortcut Resolution
138014 File May Be Truncated to Zero Bytes When Copied Onto Itself
136834 Error Copying Read-Only Files to Core SMB Server

Article ID: 174371 - Last Review: 06/22/2014 18:31:00 - Revision: 6.0

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