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I’m having a problem with one user in our system. Details are as follows:
Platform: OS X 10.10.5
Outlook version: Outlook for Mac 2016 (15.26.1)
Problem: Randomly (about 5-10 times through the work day), when the user sends an email, they get an error in Outlook for Mac, the message is not sent, and the message is put in their Drafts mailbox. The error that is displays is as follows:
The send or update operation could not be performed because the change key passed in the request does not match the current change key for the item., Cannot submit message.SaveStatus: IrresolvableConflict
PropertyConflicts: Mail could not be sent. The message has been moved to your Drafts folder.
Account name: "XXX"
Error: -19761
They then open the message from their Drafts folder and attempt to resend it. It then sends without issue.
Some additional notes:
Any advice would be appreciated.
Thanks,
Kristin.
Using older versions of Outlook for Mac in business environments
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
When I try to REST API to add attachments at same time, it also gives me this error:
Right now my walkaround way is delay the second POST request around 100 milliseconds.
Please check here for update https://stackoverflow.com/questions/47526141/412-precondition-failed-when-add-attachments-at-same-time
Another me, too.
I have a user that has been getting this error randomly in the last few days.
Outlook 2011 14.4.3 on Office 365.
-Eric
I suggest that all of you that are affected also escalate through your normal support channel to get this prioritized higher by the Exchange team.
Some additional troubleshooting information. I am running a 2011 MBP with the latest version of MS Outlook for Mac. The problem seems to occur when on the first reply message after the laptop wakes up. The problem has occurred on El Capitan (10.11) and Sierra (10.12). After the pop up message appeared (actually, it popped under) I went to my Drafts folder and found the message and resent it. The second resend actually sent the message.
I think there is an design opportunity here. I think that message that do not properly send should be kept in some type of outbox; as is the case for the iOS app and for Outlook in Windows. In Windows, if you try to close the app and the message is still in the outbox (because it hasn't sent) then you get a warning message. Something like that would be a useful feature to bring to Outlook for the Mac.
Talked with Microsoft Partner Exchange Support this morning. They know there's a key expiration mismatch on a small group of servers. It's going to have to be patched holistically which means in 4-6 months usually. If you math this issue, Apple makes up less than 10% computer market share and then how many of those are actually using Office and then how many of those are on Office365 and then who of those are on an affected server cluster.
So I'm guessing this is affecting fewer than a 1000 tenants which means reporting this up the chain is going to be difficult. It's in the queue and they know about it. I've been told it should be popping up on the dashboard soon.
I initiated the New-MoveRequest username command last night for my 3 affected mailboxes. I haven't heard back yet but it did move them to somewhat different clusters.
That seems to be a pretty simple workaround to get CEOs off your back. 25GB mailbox took about 2-3 hours to move.