Christiaan Pauw wrote: > Does anyone understand what this means or how i can fix it?
Yes. Since you're using a Greek µ (mu) character, LyX is switching to greek encoding, but you do not have the appropriate Greek fonts installed. One solution (apart from installing this font) is, as Bennett pointed out, to switch to math mode. Another one is to use the correct symbol "MICRO SIGN" instead of the (similar-looking) "GREEK SMALL LETTER MU". You can insert the correct symbol in LyX by the sequence "M-x unicode-insert 0x00b5" (where M-x opens the "mini-buffer"). Or just copy it from here: µ. If you use such units a lot, you might consider using a special package, such as SIunits. Jürgen
