Hold down the Windows key (the one with an icon that looks a little like a flag rippling in a breeze) and hit R. That should bring up the Run menu. Type 'cmd' without the quotes and hit Enter or click Ok. You should now have a window showing a command prompt. Type 'latex --version' (again without the quotes) and hit Enter. If the MiKTeX bin directory is on your system command path, you should get a few lines of output, the first of which should look something like
MiKTeX-pdfTeX 2.7.3147 (1.40.9) (MiKTeX 2.7). The central idea is that programs on your command path can be run from anywhere, without specifying the path to them. Programs not on your command path have to be started by specifying the path (or clicking an icon that contains the path). When LyX tries to configure itself the first time, it does not necessarily know where MiKTeX is installed (or even if MiKTeX is installed), so it tries to run latex.exe to see if it exists. If MiKTeX is not on the command path, Windows will not be able to run it (since LyX could not specify the directory), and LyX will think MiKTeX is not installed. If this is indeed the problem, let us know, and someone will walk you through the steps of adding MiKTeX to the command path. /Paul Firat Bilgel wrote: I opened the command prompt and under C:\>, I typed 'latex--version' (without the quotes). The program says 'latex--version' is not recognized as a file or program.
