How to fix plotting issues?

I am making some plots by plotting data that is in a big cell array. When I plot it on my personal laptop the picture is ugly (see picture)

Does anyone know how I can fix it so it looks like this (this plot was done on a computer on campus)

[Aquatris]

Are the two images have same extensions, i.e., .png or .jpg.

In your figure, you might wanna try File -> Export Setting, and from there under Properties, go to Export Setup and change Resolution (dpi) to higher value, like 600 or 1200. This might help.

[KSSV]

Did you follow the same procedure on both the machines?