Starting with the May 2019 Update (version 1903), the Windows 10 login or sign in screen background picture is blurred by default. In other words, the sign in screen doesn’t display a clear background image.
The acrylic blur effect looks quite nice actually. That said, not all users might like the blur effect.
If you would like to turn off the acrylic blur effect on the login or sign in screen background image, you will be glad to know that you can easily turn off the acrylic blur effect on the Windows 10 sign in screen.
Following are the three ways to disable the blur effect on the login or sign in screen in Windows 10 version 1903 and above.
Method 1 of 3
Disable the sign in screen blur via Settings
This is the easiest method out there to turn off the blur effect on the login screen background picture, but on the flip side it turns off the transparency effect on Start, taskbar, Settings and other areas. If you want to turn off the blur effect only on the login screen, refer to the directions in Method 2 or 3.
Step 1: Navigate to Settings > Personalization > Colors page.
Step 2: Turn off the Transparency effects option to disable the blur on the sign in screen. However, as said before, this will also disable the transparency effects on the Start, taskbar, and other areas.
Method 2 of 3
Disable sign in screen blur via Group Policy
Please note that Group Policy Editor is not available in the Home edition of Windows 10. If you are running the Home edition, please refer to the directions in Method 2 (scroll down to see).
Step 1: Open the Group Policy Editor by typing Edit group policy in Start/taskbar search field and then hitting the Enter key.
Step 2: Navigate to:
Computer configuration > Administrative templates > System > Logon
Step 3: On the right side, look for Show clear logon background policy. Double-click on the same to open its properties.
Step 4: Select the Enabled option and then click the Apply button to turn off the blur effect on the sign in screen background picture and show the clear picture.
Method 3 of 3
Turn off sign in screen blur via Registry
This method is compatible with all editions of Windows 10, including the Home.
Step 1: Type Regedit in the Start/taskbar search field and hit the Enter key. Click the Yes button when you get the User Account Control screen to launch the Registry Editor.
Step 2: In the Registry Editor window, navigate to the following folder:
Step 3: In the left pane, right-click on the Windows folder, click New, and then click Key. Name the new key System.
Step 4: Now, on the right side, right click on an empty spot, click New and then click DWORD (32-bit) Value and then name it as DisableAcrylicBackgroundOnLogon.
Step 5: Finally, double click on the newly created DisableAcrylicBackgroundOnLogon value and set the value data from the default 0 to 1 to turn off the login screen blur effect.
Set the value data back to 0 to turn on the blur effect.
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