When using MonoDevlop in Unity 4.3.2f1 (Windows 7, 64 bit) I cannot type quotation marks, tildes, accents or carets (', ", ~, `, ^). Searching on this issue shows many similar problems and were easily solved by changing the keyboard layout. I have tried changing the keyboard layout from Dutch - English US (International) to English - US but this did not resolve the problem for me.
No other software seems to be affected.
Edit: As a result I cannot quickstart the reference guide for Unity functions etc.