Q155857: Windows 95 Multiple Provider Router and Network Call Order

Article: Q155857
Product(s): Microsoft Windows 95.x Retail Product
Version(s): 95
Operating System(s): 
Keyword(s): kbnetwork win95
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft Windows 95 
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IMPORTANT: This article contains information about editing the registry.
Before you edit the registry, you should first make a backup copy of the
registry files (System.dat and User.dat). Both are hidden files in the
Windows folder.

SUMMARY
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Windows 95 provides seamless access to network services and resources using the
Multiple Provider Router. This article describes the Multiple Provider Router.

MORE INFORMATION
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The Multiple Provider Router (MPR) routes incoming network requests to the
appropriate network provider. It uses the same interface whether one or multiple
network providers is installed. It also allows for unlimited protected-mode
network providers as well as one 16-bit network provider.

When multiple network providers are installed, MPR passes the call to each
installed network provider one at a time, in a defined order. The installed
network providers are sorted by this defined order when they are loaded.
Providers with lower values are called before those with higher values. Once a
network provider returns a successful resolution of a call, additional network
providers are not tried.

The only method to change the order in which installed network providers are
called is to modify the Windows 95 registry.

NOTE: For information about how to edit the registry, view the Changing Keys And
Values online Help topic in Registry Editor (Regedit.exe). Note that you should
make a backup copy of the registry files (System.dat and User.dat) before you
edit the registry.

WARNING: Using Registry Editor incorrectly can cause serious problems that may
require you to reinstall Windows 95. Microsoft cannot guarantee that problems
resulting from the incorrect use of Registry Editor can be solved. Use Registry
Editor at your own risk.

Network provider information is stored in the following registry branch:

  HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services

Under the Services branch, there is a CallOrder key for each installed network
provider. The default CallOrder value for the Novell NetWare network provider is
00 00 00 20; the default value for the Microsoft network provider is 00 00 00
40. In this scenario, the NetWare network provider is called before the
Microsoft network provider because of its lower CallOrder value. The selection
of the primary client does not affect these settings.

Mpr.dll uses two other components, Mprserv.dll and Mprexe.exe, to facilitate
faster loading of network providers and routing of network requests. Programs
link to Mpr.dll (the smaller component), which copies API parameters to shared
memory and signals a thread in Mprexe.exe to do the work. Mprserv.dll has the
code to load net providers, route requests, and so on.

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Keywords          : kbnetwork win95 
Technology        : kbWin95search kbZNotKeyword3
Version           : 95
Issue type        : kbinfo

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