I have a MacBook with Retina display and I experience some of these screen resolution issues in Windows virtual machine:
- Windows screen resolution is low - the screen looks blurry
- Windows icons are very small or big
- Windows screen resolution is very high - everything looks tiny
- You have an external display connected to your portable Mac computer
Windows operating systems (as well as others) were not adapted to such high pixels density (DPI). Learn more about MacBook Pro Retina display: Frequently asked questions about using a Retina display
Parallels Desktop provides enhanced Retina display support for Windows 7 and Windows 8 virtual machines.
In Mac menu go to Actions (Virtual Machine in older versions) ► Configure... ► Hardware ► Video to see Resolution options for your virtual machine.
Please use the instructions below to solve display issues on a MacBook Pro with Retina display:
Note: The Resolution settings shown on the pictures apply to Windows 7 and Windows 8 virtual machines. Resolution options are different for Windows XP and Windows Vista virtual machines.
You may also learn how to change DPI scaling in Windows in this article Make the text on your screen larger or smaller
Troubleshooting: Windows image is blurry or scaled
Troubleshooting: Windows resolution is too high
Troubleshooting: Windows Fonts ans icons are too big or too small