If u havent done this, I would suggest uninstalling BlackBerry Desktop Software and go to
and choose the english version and then download. 2nd
if u have done the first suggestion and same problem then u have to clear your fontcache
Here is how to do it:
Microsoft Windows 2000/XP/Vista/7
Press and hold the "Windows" key (located between the left "Ctrl" and "Alt" keys), then tap the "E" key to open Windows Explorer.
Double-click on your local hard drive, where the operating system is installed in the left pane, then double-click to expand the "Windows" directory. Double-click on the "System32" folder.
Right-click on "Fntcache.dat" in the right pane of the Windows Explorer window and choose "Delete." Click the "Yes" button to confirm the deletion.
Close the Windows Explorer window and restart your computer.