In Windows 10, window border and title bar colors are controlled by the accent color and related personalization settings.
To change them:
- Open Settings on the PC.
- Go to Personalization > Colors (or use this shortcut: Colors).
- Under Choose your mode, select Dark or Custom (border/title bar color options are not available when Windows is in pure Light mode).
- Scroll down to Choose your accent color:
- Select Automatic to let Windows pick a color from the background, or
- Select Manual, then pick a color under Recent colors or Windows colors, or select View colors for more options.
- Below that, make sure Show accent color on title bars and window borders is turned On. This applies the chosen accent color to the window borders and title bars so they are easier to distinguish.
If a theme is forcing colors that are hard to see, switch to another theme first:
- Open Settings > Personalization > Themes.
- Under Change theme, click a different theme (for example, a default Windows theme).
- Then return to Personalization > Colors and adjust the accent color and border settings as above.
If there are unwanted custom themes:
- Go to Settings > Personalization > Themes.
- Right-click any saved theme that is not needed and select Delete (default Windows themes cannot be deleted).
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