Q177665: Path Too Long Error Message When Exceeding MAX_PATH

Article: Q177665
Product(s): Microsoft Windows NT
Version(s): winnt:3.51,4.0
Operating System(s): 
Keyword(s): kberrmsg kbui
Last Modified: 09-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation versions 3.51, 4.0 
- Microsoft Windows NT Server versions 3.51, 4.0 
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SYMPTOMS
========

Windows 95 and Windows NT 4.0 clients can expand a server directory structure
beyond MAX_PATH (256 characters) by accessing a server share and creating
directories and files through the network.

As a result, a server running Windows NT 4.0 returns the following error message
if the server administrator tries to access these files or directories locally
on the server through Windows NT Explorer:

  Can't access this folder.
  Path is too long.

If you attempt to create a new folder, you may receive the following error
message:

  Unable to create the folder '<name>'.
  The filename or extension is too long.

A server running Windows NT 3.51 shows unexpected results in File Manager such as
a general protection fault (GP fault), WINFILE crash, or display of nonexistent
directories.

Several tools and programs may also show problems when working with this
directory structure that exceeds MAX_PATH.



CAUSE
=====

Win32 programs are limited to a 256-character string size limit because of the
MAX_PATH variable. Software programs can work around this problem by passing
Win32 a path that is MAX_PATH or less. The real underlying path can then be
accessed independently of the real length of the path. In this way, a program
can access files or directories beyond MAX_PATH on the server.

RESOLUTION
==========

To resolve problems when the directory structure exceeds MAX_PATH, use either of
the following methods:

- On the server that contains the long directory structure, access these files
  and folders through a local redirection ("net use" or "subst") of the same
  share/folder that the network clients access across the network.

- In Windows NT Explorer, select the folder one level above the folder that
  returns the error. Right-click the folder returning the error and then click
  Rename. Rename the folder to reduce the number of characters used in the
  folder name.

MORE INFORMATION
================

The problem described above could not be reproduced with NTBACKUP and files and
directories that were beyond the MAX_PATH limit could be backed up and restored
successfully.

Additional query words: User Interface explore

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Keywords          : kberrmsg kbui 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT400search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS351search
Version           : winnt:3.51,4.0
Hardware          : ALPHA PPC x86
Issue type        : kbprb
Solution Type     : kbnofix

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