Important: On the Windows 8 or a newer Windows OS, the following change is typically not required.

Schema changes

The Link Assistant listing uses the Segoe UI Symbol font to display the icons. On some Windows 7 machines, the font may be an older version, e.g. 5.01 and it won't display correctly. Replace it with the same font version 6.20 and this will fix the problem.

Check in the Control Panel > Fonts if you have it. If in double, comment out the entire line  <TextBlock Text="&#xE25C;" FontFamily="Segoe UI Symbol"/>.

On some Windows 7 machines, the font may be an older version, e.g. 5.01 and it won't display correctly.

Replace it with the same font version 6.20 and this will fix the problem.