mail sent that disappears

Question

Hello

I sent an email to a customer; it has completely disappeared.

I doubted that I had sent it (not in archives/trash/deleted item recovery) but I got a feedback (automatic for absence) from the client which proves that it was indeed sent.

I noticed that the client's reply has exactly the same subject, I find it hard to believe that it could have replaced my email but I don't understand what happened and I find it worrying.

Thank you for your insights on this incident,

Answer 1

Hi @Lewis Rhiannon,

As far as I know, an automatic reply (Out of Office response) cannot replace, overwrite, or delete an email that you previously sent. It is normal for both messages to have the same subject because Outlook typically groups messages with the same conversation history into a single conversation thread. When Conversation View is enabled, the original sent message may be collapsed within the thread, making it appear as though it has disappeared.

A more likely explanation is that the sent message is being hidden by Conversation View, a filter, or it was moved/deleted by a rule, retention policy, or another connected mail client.

As a first step, please try the following:

• Turn off Conversation View in Outlook on the web: Settings > Mail > Message List > Message organization > Do not group messages
• Optionally select Show only selected message to view each email separately.
• Search Sent Items again using the recipient's email address, the exact subject, and the approximate send date/time (ensure the view is set to All and that no filters are applied.)

If you still cannot locate the message, please check Settings > Mail > Rules and review any rules that may move, archive, or delete messages automatically.

I look forward to hearing the results. If the message still cannot be found, we may need to involve your Microsoft 365 administrator to run a message trace and verify the message's delivery and routing details.

Please keep me updated on the outcome, and I'll be happy to continue assisting and provide any further guidance I can.

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