How do you get an App to open Outlook

Question

error message says I need an App to open Outlook but not where this is obtained

Answer 1

Hi, good day!

• When was the last time it worked properly?
• Have you made any changes to your computer recently?

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As a quick workaround, please try to perform an Online Repair of Office.

https://support.microsoft.com/en-us/office/repair-an-office-application-7821d4b6-7c1d-4205-aa0e-a6b40c5bb88b#id0ebd=windows_10

I look forward to receiving your update and I'm willing to collaborate with you till we resolve the issue. Do keep me informed by clicking "Add comment" below instead of Yes or No.

Answer 2

The error about needing an app to open Outlook typically appears when Windows cannot correctly find or associate the Outlook executable (for example, c:\program files\microsoft office\root\office16\outlook.exe).

From the documented cases, this has been seen when third‑party software (specifically Avast) interferes with Office apps and causes Windows to report that it cannot find Outlook.

To resolve this scenario:

1. Ensure Office is already installed (Microsoft 365 Apps, Office 2021/2019/2016, etc.).
2. If Avast antivirus is installed, update Avast to the latest version so that its fix is applied automatically, as described in the referenced article.
3. After updating Avast, restart the computer and try launching Outlook again from the Start menu or a shortcut.

If the issue was caused by Avast, the updated version should restore normal launching of Outlook without requiring any additional “app” download.

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References:

• Windows cannot find "c:\program files\microsoft office\root\office16\outlook.exe