Outlook MacOS drops all attachments sending emails

[Jan_NZ]

This is impacting an increasing number of users for us - it's infuriating dealing with MS support on this.

User adds attachments to an outbound email - either manually (from local disk) or by just forwarding an email with existing attachments.  Outlook shows attachments as present.  After hitting Send, the Sent view shows the attachment icon briefly - the icon then disappears, email goes out without any attachments.

Removing and adding back the account doesn't fix the problem.  Reinstalling outlook doesn't fix the problem...

I've raised this with MS Support several times asking for escalation...

[#2]

Hi, consider testing some of what I have in mind.
1. Manually check what is the email size limit set to.
2. Start Outlook safe mode via run -> outlook.exe/safe and test then.
3. Try saving manually "save as draft" and then send.
4. Recent security update/firewall of some sort might interfer?
results might help to better understand the issue.

[#3 · Accepted solution]

So I happened across Incident EX637339.

Basically they've known about this for months, but the !@#$ support team have instead had me jumping through nonsense hoops instead ("can you install iOS admin app?" - seriously, that was their first recommended action).

The incompetence of the support team has been staggering.

[#4]

@Jan_NZ I just started experiencing this today after months with no issues. I'm going to open a ticket also as it's infuriating.