For some reason LyX 1.5.4 no longer produces a .PDF, .PS, .DVI or LaTeX export file of either type when requested.
Perhaps it is because of an error that I have introduced in my file, but there is no error message when I request the output file. Some of my short earlier .lyx files work OK, but I am now having a similar difficulty with another .lyx file of about 45 pages that I don't think I have changed. Some operations have become quite slow too compared to earlier and other applications, even when LyX is the only open application. -- thanks in advance for any suggestions.
