In September, the new European Commission Payment Services Directive PSD2 will enter into force. Please also read the following blog post "Why there can occur problems in Outbank currently".
What does it mean for ING customers?
The EU PSD2 requires: Transfers from checking account / giro account may no longer be released via iTAN. As part of this, the iTAN list will be abandoned. Since ING only offers the iTAN method via the HBCI interface, payments via Outbank are no longer possible. Account data retrieval is still available, though.
On its website, ING explains that they “misjudged the importance of accessing the HBCI interface for our customers and the effort involved in integrating the 2-factor login. Therefore, for the foreseeable future, we will not be able to make the HBCI interface fully PSD2 compliant.” (full explanation of ING in German: https://www.ing.de/kundenservice/sicherheit/psd2/#8762904)