Here is what you try first,
To designate Outlook as your default e-mail program, follow these steps:
In Windows 95, 98, and NT 4.0:
1. On the desktop, double-click My Computer.
2. On the View menu, click Options or Folder Options, and then click File
Types.
3. Select "URL:MailToProtocol", and then click Edit.
4. In the Actions list, click Open, and then click Edit.
5. Highlight "Application used to perform action" in the dialog box, and
then press DELETE.
6. In the same box dialog box, including the quotation marks, type
""C:\Program Files\Microsoft Office\Office\Outlook.exe" -c IPM.Note /m
"%1"" (without the quotation marks).
7. Click OK, and then click Close twice.
In Windows XP:
1. On the desktop, double-click My Computer.
2. On the Tools menu, click Folder Options, and then click File Types.
3. Select "URL:MailToProtocol", and then click Advanced
4. In the Actions list, click Open, and then click Edit.
5. Highlight "Application used to perform action" in the dialog box, and
then press DELETE.
6. In the same box dialog box, including the quotation marks, type
""C:\Program Files\Microsoft Office\Office\Outlook.exe" -c IPM.Note /m
"%1"" (without the quotation marks).
7. Click OK twice, and then click Close.
If the steps above do not resolve your issue you have experience and are
comfortable working in the registry you can use the article in the
following link to try and resolve this issue,
http://support.microsoft.com/default.aspx?scid=KB;EN-US;197652.
I hope this information is helpful.
Robert Findlay
Partner Technical Lead -- Outlook/Office Setup
Microsoft Technical Support for Platforms and Business Applications
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