can't access links

The correct fix depends on whether classic Outlook shows a disabled link, does nothing, reports “Application not found,” or fails only for SharePoint or OneDrive Office-document links.

If the link is disabled or not clickable

1. Check for an InfoBar above the email saying links or external content are disabled.
2. Before enabling anything, verify the sender and inspect the destination shown when hovering over the link. Do not enable content in suspicious or unsolicited messages; external content can disclose that the message was opened and may expose you to phishing.
3. If the message is trusted, select the InfoBar option to enable the content.
4. Check whether the message is being displayed in plain text. Plain-text messages may show a URL without making it clickable; copy the full URL and paste it into your browser instead.

These are Microsoft’s documented checks for classic Outlook when links are disabled.^1^

If nothing happens or “Application not found” appears

Repair the Windows browser associations:

1. Press Windows key + I.
2. Open Apps > Default apps.
3. Select your preferred browser, such as Microsoft Edge.
4. Select Set default.
5. In Default apps, search separately for these link and file types:
   • HTTP
   • HTTPS
   • .htm
   • .html
6. Assign each one to the same browser.
7. Close and restart Outlook, then test a link.

Windows supports assigning defaults by application, file type, and link protocol.^2^ Re-selecting the browser and its HTML associations is also the recommended fix for the matching classic Outlook “Application not found” symptom.^3^

If only SharePoint or OneDrive Office-document links fail

If Word, Excel, or PowerPoint links open blank or report that the file is corrupted:

1. Restart classic Outlook first. Microsoft identifies this as a fixed service-side issue, with no client update required.
2. If it persists, right-click the link and select Open with, then choose your browser.
3. Alternatively, go to File > Options > Advanced > File and browser preferences and set Open Word, Excel, and PowerPoint files using to Desktop.
4. As a temporary workaround, copy the link into your browser or open the message in Outlook on the web.

This branch applies specifically to shared Office-document links from SharePoint or OneDrive, not ordinary web links.^4^

If none matches, provide the exact message displayed after clicking a trusted link and state whether the same link opens when pasted directly into a browser. That distinguishes an Outlook content restriction from a broken Windows browser association or a problem with the destination itself.

References

1. Links are disabled in Outlook for Windows email messages | Microsoft Support
2. Change Default Apps in Windows | Microsoft Support
3. Application not found - Microsoft Q&A
4. Office document links opened in classic Outlook might appear to be blank or open with an error | Microsoft Support