Use integration to retrieve .msg files

Hello,

We need to download .msg files (Outlook mail) from an External System using an integration that receives the document as base64.

The current problem is that Appian is able to download that document but without its extension, using the "convert base64 values to Appian documents".

I suspect it's because the MIME Type "application/vnd.ms-outlook" is not supported by the integration object as established in the following documentation I found:

• https://docs.appian.com/suite/help/25.1/Integration_Content_Types.html#document-(auto-detect)
• https://www.iana.org/assignments/media-types/media-types.xhtml

Is there any way to workaround this? Any help is appreciated

Thank you!