Some email clients not only store access data locally, but also transfer it unnoticed to external servers. As this is a considerable security risk and a data protection violation, we strongly advise against using such insecure e-mail clients. In addition, the storage of access data is a transfer of these data, which is prohibited according to the LRZ user guidelines, §4, para. 3a.

Below you will find a list of recommended clients and those that we strongly advise against. 

The list will be updated if we become aware of any further problematic clients. If you are using a client that is not listed, please check whether it is passing on your credentials.

If you have used a client that transfers your credentials: Remove your mail account from that client, uninstall it and change your password.

Safe clients

Unrecommended clients

New Outlook

Windows 

There are now two versions of Outlook: the classic version from the Microsoft Office bundle and the Windows app ‘New Outlook’. The version from the Office package can still be used without concern.

However, the new Outlook synchronises all mail accounts to the Microsoft servers. Not only are the credentials (user name and password) routed through Microsoft's servers, but also all mailbox content. This happens from the first time you try out the app.

The new version is displayed as ‘Outlook (new)’ in the Windows start menu, and a button also appears in ‘normal’ Outlook that allows you to switch to the new version. You can find more information on how to protect yourself from accidentally using the app here:

https://www.heise.de/hintergrund/Neues-Outlook-Schutz-vor-Microsofts-neugierigem-Mailprogramm-9528591.html

Further information: 

https://www.heise.de/news/Microsofts-Outlook-Datenumleitung-BfDI-will-Bericht-von-EU-Datenschuetzer-9358371.html

https://www.heise.de/news/Microsoft-krallt-sich-Zugangsdaten-Achtung-vorm-neuen-Outlook-9357691.html

Mac

The new Outlook for Mac cannot be used with an Exchange account currently. Using it via IMAP is also not recommended, as this also stores your credentials (user name and password) and all mailbox content on the Microsoft servers.

You can find out how to revert from the new version to the old version here:

https://support.microsoft.com/en-au/office/the-new-outlook-for-mac-6283be54-e74d-434e-babb-b70cefc77439#bkmk_toggle_on_off

Other unrecommended clients