Using older versions of Outlook for Mac for personal email and calendar
I agree, poor ... and embarrasing. Wasn't using legacy mode for a while but had no issues until about 4 weeks ago. Not sending attachments is crucial for a so called business tool. It is embarrassing that users are forced to switch to an old version and so being excluded from any innovation.
An interesting side note: under sent emails, the attachment can be found until Outlook is closed and restarted. After that the attachment is gone there too.