This is the message I get when I try to compile the Tutorial to dvi:
convert: unable to open image `png:C:/Users/abdel/AppData/Local/Temp//lyx_tmpdir13444a15356/lyx_tmpbuf2/20C__devel_lyx_trunk_lib_images_math_frac.png': Invalid argument.
I guess the problem comes from the double // after 'Temp' as the Windows explorer also chokes on this path, unless i remove the second slash.
Abdel.
