How to Change Default Mail Client for Internet Explorer

ID: Q154359

The information in this article applies to:

IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

SUMMARY

This article describes how to change the default mail client for Internet Explorer.

MORE INFORMATION

Changing the Default Mail Client

To change the default mail client in Internet Explorer, follow these steps:

Internet Explorer 5:

1. Start Internet Explorer.

2. On the Tools menu, click Internet Options.

3. Click the Programs tab.

4. In the E-mail box and in the Newsgroups box, click the program you 

   want.
5. Click OK.

Internet Explorer 4.0, 4.01:

1. Start Internet Explorer.

2. On the View menu, click Internet Options.

3. Click the Programs tab.

4. In the Mail box and in the News box, click the program you want.

5. Click OK.

Internet Explorer 3.0:

1. Start Internet Explorer.

2. On the View menu, click Options.

3. Click the Programs tab.

4. In the Mail box in the Mail And News area, click the program you want.

5. Click Apply, and then click OK.

Registered File Types That Are Modified When You Change

the Default Mail Client

In Internet Explorer, these changes modify the URL:MailToProtocol registered file type that is listed when you follow these steps:

Internet Explorer 4.0, 4.01, 5 for Windows 95/98 and Windows NT 4.0:

1. In My Computer, click Options (or Folder Options) on the View menu, 

   and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. The command line that controls
   the program that is used to open a MailTo Uniform Resource Locator
   (URL) appears in the "Application used to perform action" box.
Internet Explorer 4.0 for Windows 3.1:

1. In Internet Explorer, click View, click Internet Options, click the 

   Programs tab, and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. The command line that controls
   the program that is used to open a MailTo Uniform Resource Locator
   (URL) appears in the "Application used to perform action" box.
Internet Explorer 3.0:

1. In Internet Explorer, click Options on the View menu, click the 

   Programs tab, and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. The command line that controls
   the program that is used to open a MailTo Uniform Resource Locator
   (URL) appears in the "Application used to perform action" box.
Some programs may modify this setting without updating the list of programs available in Internet Explorer options for this function. For example, the Eudora Internet mail client changes the URL:MailToProtcol registered file type to the following: 

   C:\<EudoraFolder>\EUDORA.EXE /m
For additional information about behavior that occurs in Internet Explorer when Eudora is installed, please see the following article in the Microsoft Knowledge Base: 

   ARTICLE-ID: Q149617
   TITLE     : Eudora Changes Default MailTo Handler
You can also change the default program back to Internet Mail or Windows Messaging in the Mail box on the Programs tab.

Selecting Internet Mail in the Mail box changes the URL:MailToProtcol registered file type to: 

   rundll32.exe C:\WINDOWS\SYSTEM\mailnews.dll,Mail_RunDLL
Selecting Windows Messaging in the Mail box changes the registered file type to: 

   rundll32.exe url.dll,MailToProtocolHandler %l

Specifying Microsoft Outlook as the Default Mail Client

To specify Microsoft Outlook 97 as the program you want to open MailTo URL addresses, use the following steps:

Internet Explorer 4.0, 4.01, 5 for Windows 95/98 and Windows NT 4.0:

1. In My Computer, click Options (or Folder Options) on the View menu, 

   and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. Click the "Application used to
   perform action" box and press DELETE to delete the data in the box.
3. Type the following single line for the "Application used to perform 
   action" box for the Open command:

      "C:\Program Files\Microsoft Office\Office\OUTLOOK.EXE" -c IPM.Note/m
         "%1"

   NOTE: Type the quotation marks in the box.
4. To save the changes, click OK until you return to My Computer.

Internet Explorer 4.0 for Windows 3.1:

1. In Internet Explorer, click View, click Internet Options, click the 

   Programs tab, and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. Click the "Application used to
   perform action" box and press DELETE to delete the data in the box.
3. Type the following line for the "Application used to perform 
   action" box for the Open command:

      C:\OUTLOOK\EXCHNG.EXE /m
4. To save the changes, click OK until you return to Internet Explorer.

Internet Explorer 3.0:

1. In Internet Explorer, click Options on the View menu, click the 

   Programs tab, and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. Click the "Application used to
   perform action" box and press DELETE to delete the data in the box.
3. Type the following single line for the "Application used to perform 
   action" box for the Open command:

      "C:\Program Files\Microsoft Office\Office\OUTLOOK.EXE" -c IPM.Note/m
         "%1"

   NOTE: Type the quotation marks in the box.
4. To save the changes, click OK until you return to Internet Explorer.

Specifying Microsoft Outlook Express as the Default Mail Client

To specify Microsoft Outlook Express as the program you want to open MailTo URL addresses, use the following steps:

Internet Explorer 4.0, 4.01, 5 for Windows 95/98 and Windows NT 4.0:

1. In My Computer, click Options (or Folder Options) on the View menu, 

   and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. Click the "Application used to
   perform action" box and press DELETE to delete the data in the box.
3. Type the following single line for the "Application used to perform 
   action" box for the Open command:

      "C:\Program Files\Outlook Express\Msimn.exe" /mailurl:%1"

   NOTE: Type the quotation marks in the box.
4. To save the changes, click OK until you return to My Computer.

Internet Explorer 4.0 for Windows 3.1:

1. In Internet Explorer, click View, click Internet Options, click the 

   Programs tab, and then click File Types.
2. Click the URL:MailToProtocol line to select it, click Edit, click Open 
   in the Actions box, and then click Edit. Click the "Application used to
   perform action" box and press DELETE to delete the data in the box.
3. Type the following single line for the "Application used to perform 
   action" box for the Open command:

      "C:\Program Files\Outlook Express\Msimn.exe" /mailurl:%1"

   NOTE: Type the quotation marks in the box.
4. To save the changes, click OK until you return to My Computer.

Specifying Older Mail Programs

The list of mail programs that you can choose under the Internet Explorer options is made up of registry keys that outline the behavior of the program you want to use. The program should be written to add itself to the registry. If you are using an older mail program, you may want to contact the program's manufacturer to determine how to make it the default mail program.

How to Modify the Registry

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

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).

This section describes how to add your program to the list of Internet service programs available to Internet Explorer.

By changing the values that are stored in the registry for extended services such as mail and news, it is possible for Internet Explorer to start programs that provide specialized Internet services. By appending new key definitions to the end of the registry path, it is possible to add other programs to the menu items that are available within Internet Explorer.

Adding Client Programs:

For example, to include a mail client program in the list of available programs:

Register your client programs in the registry: 

   HKLM\SOFTWARE\Clients\Mail\<Your_Mail_Client_Name>
Define the client and the path to the program to be started by Internet Explorer: 

   HKLM\SOFTWARE\Clients\Mail\<Your_Mail_Client_Name>\shell\open\command\ 
      "C:\Program Files\<Your Directory Name>\<YOUR_MAIL_CLIENT_NAME.EXE>"
Additional query words: 3.00 4.00 5.00 
Keywords          : msiew95 msiew31 msiew98 
Version           : 3.0 3.01 3.02 3.02a 4.0 5.0 98
Platform          : WINDOWS
Issue type        : kbhowto

Last Reviewed: March 18, 1999