Use brute force: hack the Windows Registry
As long as you’re happy editing the Windows Registry, you can take more drastic steps but, as is always the case when working with the Registry, make sure to create a System Restore point before beginning and, preferably, a full, verified backup of your system before you do.
We’ll start by disabling system pop-ups. Launch Registry editor (type “regedit” into the search box and pick the first result), and navigate through the Registry tree to “HKEY_CURRENT_USER\ Software\Microsoft\ Windows\CurrentVersion\ Explorer\Advanced”. Once you’re there, pick “DWORD (32-bit) Value” from the Edit menu’s New sub-menu (or right-click any blank area in the main pane) and name it “DWORD EnableBalloonTips”. Make sure that you match the capitalisation. That should be all you need to do, as by default the DWORD’s Value should be set to zero, but right-click it and pick Modify just to make sure.
Now we need to do the same for application pop-ups that are delivered from local APIs or the cloud via Windows
ABOVE When it comes to disabling system pop-ups, Windows Registry is your trusted, powerful friend
Notification Service – or anything that’s not Windows itself. These notifications are appropriately known as “toasts”, perhaps due to the fact that they pop up, like bread from a toaster.
Go back through the Registry tree to “HKEY_ CURRENT_USER\ Software\Microsoft\ Windows\CurrentVersion\ PushNotifications”, where you should find an existing DWORD for ToastEnabled. Double-click to edit it and set the Value data to zero (“0”). If the key doesn’t already exist, create it and then set the value.
Close the Registry editor and restart your PC for the settings to take effect. You can make sure that they worked correctly by performing any action that would usually spawn a pop-up, such as updating files in Dropbox using the web browser while the Dropbox client is active on your machine.
Exit the Registry and restart your PC.
“Make sure to create a System Restore point before beginning and a full backup”