winmail.dat komplett deaktivieren (ab Outlook 2007 SP2 und höher)

Eine gute Beschreibung dazu findet man (aktuell) unter

[http://www.slipstick.com/problems/outlook-is-sending-winmail-dat-attachments/](http://www.slipstick.com/problems/outlook-is-sending-winmail-dat-attachments/ "http://www.slipstick.com/problems/outlook-is-sending-winmail-dat-attachments/")

If nothing seems to be working and you use Outlook 2007 SP2 or Outlook 2010 or 2013, you can use a registry value to end TNEF encoding once and for all. This will affect your ability to use features that require TNEF encoding, including Voting and Meeting Requests in native Outlook format. (Ready-to-use .reg files are available below.)

o 2. Close Outlook o 4. Start Registry Editor (type regedit in the Start Search box or Start menu, Run command and press Enter) o 6. Locate the following registry key: **In Outlook 2007:** |

`HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Preferences`

| |---| **In Outlook 2010:** |

`HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences`

| |---| **In Outlook 2013:** |

`HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Preferences`

| |---| o 5. Add a new DWORD named DisableTNEF. o 7. Double click on DisableTNEF and in the Value data box, type 1 o 9. Close the Registry editor and Restart Outlook More information on this registry fix: [When you use Outlook 2007 to send an e-mail message, the recipient of the message sees an attachment that is called Winmail.dat](http://support.microsoft.com/kb/958012 "http://support.microsoft.com/kb/958012") Hotfix for pre-Outlook 2007 SP2 to enable the registry fix: [Description of the Outlook 2007 hotfix package (Outlook.msp): October 28, 2008](http://support.microsoft.com/kb/957692 "http://support.microsoft.com/kb/957692")