NotiRewind
What was that Windows notification? Find who sent it and whether it's safe
Something popped up in the corner of the screen and was gone before you could read it. Here is where to look.
See the sender in the notification center
Press Windows key + N to open the notification center. Notifications are listed under the name of the app that sent them. If there's an arrow next to the time, select it to see more details. If the sender is an app you don't recognize, select it under Settings > System > Notifications > Notifications from apps and other senders and turn its notifications off (Microsoft Support).
If it isn't there, Where is notification history in Windows 11? explains why notifications leave the notification center.
If it was a Windows Security alert
For a detected threat or a warning that some protection was turned off, open the Windows Security app and select Protection history. It lists the actions Microsoft Defender Antivirus took, potentially unwanted apps it removed, and important services that are off (Microsoft Support).
Protection history keeps events for two weeks. You need admin rights on the PC to see the details of a threat.
If it was about an update or a driver
Settings > Windows Update > Update history lists the updates that were installed and when (Microsoft Support). Drivers installed through Windows Update appear there too, with names like "Logitech Driver Update" (Microsoft Support).
If it asked you to restart, see Missed the Windows Update restart notification?
If it said "virus found" and gave a phone number
Error and warning messages from Microsoft never include a phone number. Some websites show fake errors in full screen so they look like they came from Windows (Microsoft Support). Don't call the number.
If Defender really found something, it's recorded in Protection history. If the same warning keeps arriving as a browser notification, you've allowed that site to send notifications. How to see and stop Chrome and Edge website notifications shows how to block it.
Catch the next one
NotiRewind saves notifications that reach the notification center, with the time and the app that sent them. If a banner disappears, you can still read the full text from the tray icon or with Ctrl+Alt+N.
Only notifications that reach the notification center can be saved. Notifications from before installation are saved only if they are still in the notification center. If an app removes its own notification right after showing it, it may not be saved.