The default icon size in Windows 7/Windows Server 2008 R2 is set to medium by default, which is larger than previous Windows operating system versions. This may need to be reduced to provide a desired look and feel.

Methods that worked in previous operating system versions do not appear to work e.g.

[HKEY_CURRENT_USER\Control Panel\Desktop\WindowMetrics]
"Shell Icon Size"="16"

DesktopIconSize.exe can be used to reduce or enlarge Desktop icons from the command line:

http://theether.net/download/Microsoft/Windows/DesktopIconSize.exe

C:\>DesktopIconSize.exe
Change the Desktop icon size in Vista or later

Usage: DesktopIconSize.exe <+/- icon size>
e.g. Medium to Small: DesktopIconSize -4
e.g. Medium to Large: DesktopIconSize +7

(C)2010 Jamie Morrison http://theether.net/contact

Based on code by Rei Resurreccion
http://www.codeproject.com/KB/files/deskicon.aspx

This will give the a similar effect to CTRL scrolling on the mouse to resize the desktop icons.

This can be run once by creating a Group Policy Preference for the following registry key:

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce]
"DesktopIconSize"="C:\Windows\DesktopIconSize.exe -4"

The following two options should be set, to ensure it is only applied once:

- Run in logged-on user’s security context
- Apply once and do not reapply

Programmatically resize Desktop icons to a small list in Windows Vista and Windows 7
http://www.codeproject.com/KB/files/deskicon.aspx