I have a paper written and edited in LyX.
On a printing today I noticed that all 'fi' combinations are not visible.
The characters are in the document and displays in the PDF but doesn't print.
Is this a printer, LyX or PDF problem?
I have a paper written and edited in LyX.
On a printing today I noticed that all 'fi' combinations are not visible.
The characters are in the document and displays in the PDF but doesn't print.
Is this a printer, LyX or PDF problem?
This is a font problem, but might be also related to your printer/its driver.
The 'fi' character (+ 'ff', 'fl', ...) is a ligature, i.e. a combination of two characters created to optimize the space between the characters. Some fonts do not include these special characters and they also tend to go missing in conversions. Your printer driver might convert the PDF to Postscript for printing and something gets messed out at this point. Maybe your font is not Postscript compatible. Should you load any kind of font packages try to disable them and see if the print-out changes.
You should also ensure that you use the font with a proper encoding, e.g. by loading:
\usepackage[T1]{fontenc}
in the preamble.
You might try to use another (at best PostScript) fonts which have the ligatures included. Some possible choices would be psnfss (Postscript New Font Selection Scheme), pxfonts (Palatino style) or txfonts (Times style). Simply load them like packages, e.g. \usepackage{psnfss}.
The ligatures can also be disabled globally using: (needs pdflatex)
\usepackage{microtype}
\DisableLigatures{encoding=*,family=*}