Emails going into the Conversation History folder instead of the Inbox are typically being filed there by Skype for Business/Lync conversation history, not by Outlook mail rules.
To stop mail from being diverted and to restore normal behavior, use these steps:
- In Outlook, check the Conversation History folder location:
- If the folder is missing or in the wrong place (for example, under Inbox), recreate it so Skype for Business/Lync can use it correctly and not interfere with normal mail delivery:
- Exit Outlook on all devices.
- Download and run MFCMAPI.
- Select Tools > Options and enable Use MDB_ONLINE when calling OpenMsgStore.
- Select Session > Logon, choose the profile, and open the mailbox.
- Expand Root Container > Top of Information Store, then select Inbox.
- In the Tag column, locate tag 0x35E90102 (Conversation History folder EntryId) and delete that line.
- Close MFCMAPI. Skype for Business/Lync will recreate the Conversation History folder in the correct place.
- In Lync/Skype for Business, verify conversation history settings so only IM/call history is saved there, not email:
- Open Lync/Skype for Business.
- Go to Options > Personal.
- Check Save IM conversations in my email Conversation History folder. If this option is disabled or controlled by policy, contact the organization’s support.
- If Skype for Business features such as conversation history or voicemail are failing and causing odd behavior, check Deleted Items:
- In Outlook, open Deleted Items and remove any subfolders under Deleted Items.
- This resolves issues where oversized items under Deleted Items prevent proper integration with Exchange and Outlook features.
After these steps, new email should continue to arrive in the Inbox, while only IM/call history is stored in Conversation History as designed.
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