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Baixe o hotfix
Para habilitar o hotfix, siga estas etapas:
> 1. Exit Outlook 2007.
> 2. Start Registry Editor.
> * In Windows Vista, click Start
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> the Start button
> , type regedit in the Start Search box, and then press
> ENTER.
>
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> User Account Control permission
> If you are prompted for an administrator password or for
> confirmation, type the password or
> provide confirmation.
> * In Windows XP, click Start, click Run, type regedit in the
> Open box, and then click OK.
> 3. Locate and then click to select the following registry key:
> HKEY_CURRENT_USER\Software\Microsoft\Office.0\Outlook\RPC
> Note If the RPC key does not exist, follow these steps:
> 1. Right-click the Outlook key, point to New, and then click Key.
> 2. Type RPC, and then press ENTER.
> 4. After you select the key that is specified in step 3, point to New on
> the Edit menu, and then click DWORD
> Value.
> 5. Type UseWindowsUserCredentials, and then press ENTER.
> 6. Right-click UseWindowsUserCredentials, and then
> click Modify.
> 7. In the Value data box, type the value that you want to use, and then
> click OK.
>
> Note When you set the UseWindowsUserCredentials value to 1,
> only the user's desktop credentials
> will be used. The following scenarios
> may help you determine the value that
> you want to use.
> * Account: Domain
> UseWindowsUserCredentials: 0 (or not present)
> Protocol: TCP, HTTP with NTML authorization
> Result: Connect to Microsoft Exchange without prompting
> for user credentials.
> * Account: Non Domain
> UseWindowsUserCredentials: 0 (or not present)
> Protocol: TCP, HTTP with NTLM authorization
> Result: Prompt for user credentials and connect to Microsoft
> Exchange.
> * Account: Domain
> UseWindowsUserCredentials: 1
> Protocol: TCP, HTTP with NTLM authorization
> Result: Connect to Microsoft Exchange without prompting
> for user credentials.
> * Account: Non Domain
> UseWindowsUserCredentials: 1
> Protocol: TCP, HTTP with NTLM authorization
> Result: Does not prompt for user credentials, and will not
> connect to Microsoft Exchange. Remains
> in the disconnected state,
> occasionally trying to connect.
> * Account: Domain
> UseWindowsUserCredentials: 1
> Protocol: HTTP with Basic authorization
> Result: Prompts for user credentials and successfully connects
> to Microsoft Exchange. Additionally,
> it will continue to prompt you if you
> mistype your password.
> * Account: Non Domain
> UseWindowsUserCredentials: 1
> Protocol: HTTP with Basic authorization
> Result: Prompts for user credentials and successfully connects
> to Microsoft Exchange. Additionally,
> if you mistype your password, it will
> continue to prompt you.
> * Account: Domain
> UseWindowsUserCredentials: 1
> Additional Steps: When you configure the profile, select Always
> prompt for username and password.
> Result: Prompts for user credentials and successfully connects
> to Microsoft Exchange.
> 8. On the File menu, click Exit to exit Registry Editor.