Printing Issues between My computer and a Co-Workers

[Emily25261373a19m]

Hello, having issues with a co-workers documents when they are printed from their computer via Adobe Acrobat. When printed from my computer, there are no issues. I have checked all printer settings and all are identical. 

The issue is that my co-workers computer prints grey/purple coloured boxes in spaces that should be white. Please see attached photos for example of issues. First image shows the colour issue, second photo is the correct printed image. Only shows up when printing, not when displayed on the computer. 

Just wondering if anyone has any insight towards fixing this issue?