You upgrade to Windows Live Messenger 2009 or Windows Live Mail 2009 on a computer that is running a Windows operating system. After you sign in to the Windows Live application, some or all of the contacts are missing from the contact list.
Note This issue does not occur if you roll back to the earlier version of the Windows Live application.
This issue occurs because your contact list is not migrated correctly from the earlier version of the Windows Live application. .
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To resolve this issue, change the DWORD value of the following registry key entry to 0x0000000B (11):
HKEY_CURRENT_USER\Software\Microsoft\Windows Live Mail\Settings Upgraded
To do this, follow these steps:
Start Registry Editor.
Windows Vista or Windows 7:
Click Start, type regedit in the Start Search box, and then press ENTER.
If you are prompted for an administrator password or for confirmation, type the password or provide confirmation.
Click Start, click Run, type regedit, and then press ENTER.
Locate and then click the following registry subkey:
HKEY_CURRENT_USER\Software\Microsoft\Windows Live Mail
Double-click the Settings Upgraded entry.
In the Value data box, type B, and then click OK.
Exit Registry Editor.
Microsoft has confirmed that this is a problem in Windows Live Messenger 2009 and in Windows Live Mail 2009.