Dear @Justin Gingrich,
Thank you for posting your question in the Microsoft Q&A forum.
I understand how inconvenient it must be to lose the ability to drag and drop attachments directly from New Outlook to your ERP system.
Unfortunately, New Outlook doesn’t support automatic downloading of attachments. You only can manually choose “Download” to download the file to your local device and then drag and drop it into your ERP system.

Thank you again for raising such a thoughtful question. It highlights an important area where New Outlook could improve.
While this may not be the ideal answer you were hoping for, your feedback is truly valued. As community moderators, our role is to guide users toward helpful resources and support channels, though we don’t have direct influence over product design or access to internal development timelines.
The most effective way to share your experience and advocate for improvements is through Microsoft’s official feedback channel. You can submit your suggestion to our product team via the Microsoft 365 Feedback Hub > Send Feedback > Describe your proposal in detail.
Sharing your experience through this channel is the most impactful way to advocate for a change that would benefit you and other users.
Thank you again for your patience and for bringing this to our attention. While I can't change the product's design, please don't hesitate to reach out if you have any other questions about its current functionality.
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