Welcome Jook _,
I know how frustrating it can be when you want to enable the Aero (Aero Glass) visual effects on your Dell Vostro 15 3549 running Windows 7.
Since Windows 7 is End of Service, this product has been EOS, but you can still try these workaround steps below:
Option 1: Verify that your Windows 7 edition supports Aero
- Right‑click on the desktop
- Select Personalize
- Check whether Aero Themes are available
Option 2: Check and update the graphics driver
- Open Device Manager from the Start menu
- Expand Display adapters
- Right‑click your graphics device and select Update Driver
- Install a driver that supports Windows Display Driver Model (WDDM)
Option 3: Ensure Desktop Window Manager service is enabled
- Press Windows key + R > type:
services.mscand press Enter - Locate Desktop Window Manager Session Manager
- Make sure the Startup type is set to Automatic and the service is running
Option 4: Apply an Aero-compatible theme
- Right‑click on the desktop
- Select Personalize
- Choose one of the default Windows Aero themes
- Avoid High Contrast themes, as they disable Aero effects
Option 5: Recalculate Windows Experience Index
- Open Control Panel
- Select System
- Select Windows Experience Index
- Click Re-run the assessment
- Aero typically requires a graphics subscore of 3.0 or higher
I really hope that the information I gave above was helpful to you. Please feel free to reply below and let me know if you have further concern on this matter.
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