On a Windows 7 machine, Right-click on the desktop and click Personalize Click Display to bring up the DPI adjustment window, which is titled "Make it easier to read what's on your screen." Change from the current setting to a larger or smaller setting, then click "Log off now."
When you perform these steps, sometimes the fonts may not all get scaled properly. Certain fonts in the user inteface may be either too large or too small.
This is the result of a timing issue between the Explorer and Winlogon processes. When this condition happens, certain fonts get resized twice.
Change the DPI setting again to reset the font to a normal size. Note you may need to change the setting a few times.