In February 2026 Microsoft acknowledged a known issue in classic Outlook for Windows: the mouse pointer can vanish while you move it over the app, even though the pointer still works underneath. It is a desktop annoyance rather than a security flaw, but it matters to anyone who supports Microsoft 365 users, and to developers who ship desktop apps with an embedded WebView2 surface, because Microsoft's troubleshooting steps point at that component.

What happened

Microsoft published a support article titled "Mouse pointer disappears when hovering over classic Outlook" on 19 February 2026 and updated it on 27 February. It says the pointer can disappear while it is over the Outlook interface. The pointer is still active, so the message under it in the list still changes colour, but you can't see where you are clicking. Microsoft says the same behaviour has been reported in OneNote and, to a lesser extent, other Microsoft 365 apps.

According to Office Watch, users had been reporting the problem since around December 2025, roughly two months before Microsoft acknowledged it. When the article was published, its status was "under review". The Outlook team said it was working on a fix but gave no build number or date.

Who is affected

Users of classic Outlook for Microsoft 365 on Windows. The new Outlook for Windows is not mentioned.
OneNote users, plus a smaller number of people using other Microsoft 365 desktop apps.
Help desks and Microsoft 365 admins, who will get the tickets. Microsoft has not said which versions, builds or update channels are affected, so you can't rule a machine in or out just by its build.

What it means for developers and engineering teams

For most engineering teams this is an endpoint-support issue, not a code issue. Microsoft has not published a root cause. What stands out is the evidence it asks for: admins opening a support case should capture WebView2 WPR (Windows Performance Recorder) traces while reproducing the problem, following the WebView2Feedback diagnostics guide, and include a screen recording. That strongly suggests Microsoft is looking at the Chromium-based WebView2 control that Office apps now embed for parts of their UI. It does not prove WebView2 is the cause.

If you build Windows desktop apps that host WebView2, keep this in mind as a pattern. Cursor and focus handling at the boundary between native windows and an embedded browser surface is a common source of odd input bugs, and these bugs often show up after a runtime update that you didn't ship. Two practical lessons:

Learn the WebView2 tracing workflow before you need it. Microsoft's own support teams ask for these traces first, and so will you when a user reports something you can't reproduce.
Track which WebView2 Runtime version your users have. With the Evergreen runtime, the browser engine inside your app can change without a release from you.

What to do now

Use Microsoft's workarounds to get users working again:
- Hover over a message until it highlights, then click it. This can make the pointer reappear.
- Open PowerPoint, click into an editable area of a document, then switch back to Outlook.
- Restart the computer.
Give the help desk a script. Users tend to describe this as a frozen app or a dead mouse. A known-issue note with the three workarounds saves a lot of hardware swaps.
Open a Microsoft support case if it affects many people. Route it to the Outlook team and attach WebView2 WPR traces captured while you reproduce the issue, plus a screen recording, as the support article asks.
Record the WebView2 Runtime version on affected machines (Settings > Apps > Installed apps > Microsoft Edge WebView2 Runtime) so you can tell whether a runtime update lines up with the start of the reports.
Check the Microsoft support article again before escalating, because the fix status and any affected-build details will be published there.

What happened

Who is affected

What it means for developers and engineering teams

What to do now

Sources

TechLogHub Blog — Page 25 of 25

Classic Outlook bug hides the mouse pointer; Microsoft points to WebView2 traces