This scaling problem in Adobe Muse is encountered when you set Windows Scale settings to 125%. Adobe Muse renders its user interface at 100%, 150%, or 200% depending on the Windows Scale settings and the environment variable. If the environment variable is not set and the Windows Scale setting is set to 125%, then the Adobe Muse user interface displays at 150% resolution.

If you prefer to keep your current Windows Scale settings, you can set an environment variable to force Adobe Muse to render its user interface at 100%.

Add custom Environmental Variable value

Windows Scale settings impact the overall Windows screen display. You can add Environmental Variable value to control only settings for Adobe Muse and not impacting the overall Windows display.

1. Right-click the Computer on your Desktop and Choose Properties.
2. In the System window, click Advanced System Settings in the left pane.
3. In the System Properties window, select the Advanced tab and click Environment Variables.
4. Click New in the System Variables section. You can also set it in User Variables section, if you want to keep the change limited to currently logged-in user.
5. In the New System Variable dialog box, enter MUSE_UI_SCALE_FACTOR in the Variable Name field.
6. Enter 1 in the Variable Value field.
7. Click OK.