You Receive a "Windows Cannot Open This File" Message When You Try to Use a Contact List in Messenger 4.5 (309574)

SYMPTOMS

In Windows Messenger 4.5, if you double-click an exported Messenger contact list (.ctt) file, you receive the following message:

Windows cannot open this file.
File: FileName.ctt
To open this file, Windows needs to know what program created it. Windows can go online to look it up automatically, or you can manually select from a list of programs on your computer.
What do you want to do?
- Use the Web service to find the appropriate program.
- Select the program from the list.

If you use the Web service, the Web service does not recognize the file type.

CAUSE

This behavior occurs because the .ctt file name extension is not registered when you install Windows Messenger 4.5.

WORKAROUND

To work around this behavior, import an existing contact list in Windows Messenger 4.5 by following these steps:

In Windows Messenger 4.5, on the File menu, click Import Contacts from a Saved File.
Click the contact list that you want to import, and then click Open.
If a message informs you that the contact list was saved successfully, click OK.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

In Windows Messenger 4.6, if you double-click an exported Messenger contact list (.ctt) file, you receive the following message:

Caution: You are attempting to open a file of type 'Messenger Contact List' (.ctt).
You cannot open this file directly. You must open Messenger and select "Import Contacts..." from the "File" menu.
If you still want to open the file, click Open With, otherwise, click Cancel.