You cannot double-click to open an Excel attachment in Outlook 2007

Excel 2007

1. Close the message.
2. Start Excel.
3. Click the Microsoft Office Logo Button, click Excel Options, and then click Advanced.
4. Under the General tab, click to clear the Ignore other applications that use Dynamic Data Exchange (DDE) option, and then click OK.
5. Exit Excel.

Now you can double-click the attachment to open it in Excel, and you can save it to your hard disk, and then double-click the file to open it.