I appear to have the same problem as Luis described in this thread:
http://www.mail-archive.com/lyx-users@lists.lyx.org/msg60058.html
However, I am having problems implementing the resolution detailed by Paul
Rubin. I would have replied within that thread, but for some reason the
'Reply via email' button at the bottom of the thread is not working in any
of my browsers (FF, Opera, and IE)
To clarify, I am running Windows XP and Lyx 1.5.6 (1.5.6-1 installer), and I
have experienced the same errors Luis described:
"LyX: Document class not available" when I open templates, etc., and
"No information for exporting the format DVI"
"No information for exporting the format PDF"
"No information for exporting the format Postscript"
when I try to perform those actions.
I originally tried to direct LyX to use TeX from an existing install of
LiveTeX, and had these errors. I then reinstalled LyX and directed the
installation to install MiKTeX
(2.7). The first time it installed MiKTeX after the install
completed, I received a message that said that MiKTeX had NOT been
installed. Confused, I answered the prompt by telling it to install
MiKTeK. The install began again, but it would not install to the
default folder (MiKTeK 2.7 in Program Files) because it was not empty,
so I directed it to install to 'MikTek 2.7_'. I received the same
message at the end of this install, but opted to continue anyway. My
problem may be related to this.
MiKTeK appears to be working, or at least all of the programs in the
program menu are working, and they point to the install in 'MikTeX 2.7_'
I followed the guidance provided by Paul, in spite of my limited DOS
abilities.
I ran 'kpsewhich article.cls' and the command prompt responded with the
location of article.cls:
C:/Program Files/MiKTeX 2.7_/tex/latex/base/article.cls
I interpreted that as MiKTeX being on the system path, so I relocated the
dos prompt as directed by Paul to:
C:\Documents and Settings\Adam\Application Data
At this point I tried to
run python configure.py, but I got an error. I entered the following
text into the command prompt at \Application Data:
C:\program files\lyx15\python\python.exe C:\program
files\lyx15\resources\configure.py
and I received this output:
'C:\program' is not recognized as an internal or external command, operable
program, or batch file.
I assume I need to provide some sort of command to tell it to run python,
but I don't know enough DOS to do so. I tried to use the 'help' command to
find the command to use here, but nothing looked appropriate.
Of course, this also may not address the problem.
Thanks, and I look forward to using LyX.