If the lost chats were in Skype for Business or Lync, there are two main ways to try to get them back: from the app’s own history view and from Outlook’s Conversation History folder. There is also a way to reach a human by phone.
1. Check conversation history in Skype for Business
- Open Skype for Business.
- At the top of the main window, above the search box, select the Conversations tab.
- This shows all incoming and outgoing instant messages and meetings in chronological order, with the most recent at the top.
- Phone calls also appear in this list.
- To narrow what is shown:
- Click Missed to see the 100 most recent missed conversations.
- Click Calls to see the 100 most recent incoming and outgoing audio and video calls.
To find chats with a specific person:
- In the Contacts list, right‑click the person.
- Select Find Previous Conversations.
- Outlook opens and shows that person’s conversations with you in the Conversation History folder.
- In Outlook, use the search box at the top of the window and type words that were in the conversation to locate a specific chat.
If nothing appears in the Conversations tab after the reboot, the local cache may have been cleared, but the items may still exist in Outlook’s Conversation History folder (see next section).
2. Check conversation history in Lync
If the chats were in Lync instead of Skype for Business, the process is similar:
- Open Lync.
- Above the search box, click the Conversations tab.
- All conversations are listed in chronological order, most recent at the top.
- Phone calls appear in this list; missed calls that went to voicemail appear under the Phone view (click the Phone icon).
- To filter:
- Click Missed to list only missed conversations.
- Click Calls to list only phone calls.
To find a previous conversation with a specific contact:
- In the Contacts list, right‑click the contact.
- Click Find Previous Conversations.
- Outlook opens the Conversation History folder filtered to that contact.
- Use the Outlook search box to search by keywords that were in the chat.
3. Verify that conversation history is actually being saved (Lync)
If nothing appears in Outlook or in the Conversations tab, conversation history might not have been enabled:
- In the Lync main window, click the Options button, then select Personal.
- In Personal information manager, look for the checkbox Save IM conversations in my email Conversation History folder.
- If the checkbox is missing or dimmed, conversation history is not available for that account.
- If the checkbox is present but not selected, history was not being saved. Selecting it will only affect future conversations.
- If the checkbox is selected, Lync should be saving conversations to Outlook’s Conversation History folder.
If conversation history was disabled or not available, past chats that were only stored locally may not be recoverable after a reboot or profile reset.
4. If chats were in Outlook’s Conversation History
When conversation history is enabled for Skype for Business or Lync and the environment uses Exchange/Outlook:
- Open Outlook.
- In the folder list, open the Conversation History folder.
- Browse the list (sorted by date) or use the search box to search by:
- Contact name
- Keywords from the chat
- Approximate date range
This is often where “lost” chats reappear even if they no longer show in the client’s local view after a reboot.
5. Speaking to someone by phone
To talk to a human by phone about account or data issues, use the Microsoft customer service phone contact page referenced in the Microsoft Q&A guidance:
- Go to the customer service phone numbers page.
- Choose the region and follow the instructions to get a phone number or callback option.
This route is appropriate if:
- The account is managed by Microsoft consumer services and self‑service recovery is not resolving the issue.
- Direct assistance is needed beyond what the community and documentation can provide.
If the chats were in a different app (for example, a non‑Microsoft messenger) or if conversation history was never enabled, there may be no supported way to restore them after a reboot.
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