In new Outlook for Windows, drag and drop of attachments is still supported, but behavior can differ from classic Outlook and from app to app.
From the provided information:
- New Outlook supports drag and drop of attachments out of messages, including dragging an attachment to the desktop or other locations.
- Drag and drop is also supported for opening certain file types (.eml, .msg, .oft) by dropping them onto the reading pane.
However, there is no documented guarantee that drag and drop from new Outlook into arbitrary third‑party applications (such as an ERP client) will behave identically to classic Outlook. Classic Outlook is MAPI‑based and integrates differently with other Windows applications, while new Outlook is not fully MAPI‑compliant and has known integration differences with desktop apps.
So, it is expected that drag‑and‑drop behavior into some external applications may not work the same way in new Outlook as it did in classic Outlook. In such cases, a workaround is to first drag the attachment to a folder (for example, the desktop or a file share) and then import or attach it from there into the ERP system.
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