freshly installed lyx on arch linux, and the 'view buffer' button as well as the shortcut (Ctrl+r) are disabled, I read somewhere that it's necessary to set the default output format at:
'Tools -> Preferences -> File Handling -> File Format'.
However, the only options I have there are DVI, and DVI(LUATEX), and when I choose any of them it fails to compile.
I want to compile a pdf so I mye questions is:
How do I add a default option to compile to a PDF?
A guess of mine (after searching a bit more) is to add a path to the pdflatex compiler, or something like that, under 'Paths', but I don't know what path that would be.
Best Answer
I had a similar issue occur, where some configuration error kicked out the converters needed for PDF export (see NivPgir's answer).
In order to restore PDF as output format however, I had to change the setting Tools → Preferences → File Handling → File Formats → Default Output Formats → With TeX fonts back to PDF (pdflatex).