Using MS365 and lost outlook.exe on W10 computer

Question

Using MS365 (renewed today) have been in the process of moving to W11 computer and lost my outlook.exe. on the 10. Lost all access to everything. MS agent had me do a reinstall and of course it didn't work. Then MS would not help me get outlook.exe back because they don't support W10. So, I worked with copilot and we did the entire samba everything I see recommended by MS to get my corrupted office 16 back. At least that is what we assumed is going on. No dice - can only get true uninstall reinstall if you are enterprise. Now I see there is a comment that they know it is a bug. BTW I have multiple cases "closed without resolution." What is happening? I pay for 365, my computer is legal to 10/26 and I can't get a solution that works anywhere. Meantime all my outlook histories are MIA.

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Moved from Microsoft 365 and Office | Other

Answer 1

Hi Lyn Q,

Welcome to Microsoft Q&A.

I understand how frustrating this is, especially when Outlook history seems to be missing. I can see you've already been through several troubleshooting attempts, so I'll focus on the most reliable paths forward for Microsoft 365 Personal/Family on Windows 10.

Based on what you described, this usually happens when Classic Outlook (OUTLOOK.EXE) isn't actually installed or the Microsoft 365 Click-to-Run install is corrupted, and sometimes only New Outlook remains visible.

Here are the most reliable steps for Microsoft 365 Personal/Family:

Check if OUTLOOK.EXE exists

Look in:

• C:\Program Files\Microsoft Office\root\Office16
• C:\Program Files (x86)\Microsoft Office\root\Office16

If you find OUTLOOK.EXE, create a shortcut and launch it.

Do a deeper uninstall (available for Microsoft 365 Personal/Family)

1. Uninstall Microsoft 365 from Settings > Apps (or Control Panel).
2. If Outlook.exe still doesn't return after reinstall, use Microsoft's official uninstall support tool to remove leftover components, then reboot and reinstall:

• Uninstall Office: Uninstall Microsoft 365 or Office from a PC
• Reinstall Microsoft 365: Download, install, or reinstall Microsoft 365 or Office 2024 on a PC or Mac

If you only see "New Outlook," reinstall Classic Outlook

Follow Microsoft's steps to install/reinstall Classic Outlook: Install or reinstall classic Outlook on a Windows PC

About "missing history"

• If your account is Outlook.com/Exchange/IMAP, your mail should re-sync once the account is added back.
• If you used POP or local archives, look for .PST files on the old drive (commonly in Documents\Outlook Files or AppData\Local\Microsoft\Outlook) and then open them in Classic Outlook via File > Open & Export > Open Outlook Data File.

Note: Windows 10 support ended on Oct 14, 2025, which means Microsoft may not provide assisted support for Windows 10-specific issues, but the steps above typically restore Outlook if the issue is install corruption.

For reference: Windows 10 support has ended on October 14, 2025

If you reply with whether your email account is POP or IMAP/Exchange (and whether you see "New Outlook" only), I can point you to the exact recovery path for your data.

Please let me know if this proves useful to you, or if you would like further assistance.

I'm looking forward to your reply.

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Answer 2

Thank you for all the advice which could be helpful to someone else, however I have never even heard of avast, let alone put it on my computer, and working with copilot I did everything you recommended. Sometimes twice as I went from wifi to ethernet to provide a clean download. Nothing worked. I am very frustrated.