BUG: OpenFile() Fails When UNC Name Longer Than 11 Characters

The information in this article applies to:

• Microsoft Windows Software Development Kit (SDK) for Windows versions 3.1 and 3.11

SYMPTOMS

OpenFile() successfully opens files with universal naming convention (UNC) names when the server portion of the name is 11 characters or shorter, but fails to open files when the server name is longer than 11 characters. Error code number 2, "File not found," is placed in the nErrCode member of the OFSTRUCT structure passed to OpenFile.

CAUSE

OpenFile() validates filenames before opening them, and in the case of UNC names, allows server names that are 11 characters or shorter only. No attempt is made to open a file with a UNC name longer than 11 characters.

RESOLUTION

To open files with UNC names when the server name is longer than 11 characters, use _lopen().

STATUS

Microsoft has confirmed this to be a bug in the Windows SDK versions 3.1 and 3.11. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

This is not a problem under Windows NT WOW or under Windows 95.

MORE INFORMATION

This problem also affects the File Open common dialog box, because GetOpenFileName() calls OpenFile().