I have had the same problem for the past couple of weeks.  I tried to
access some research announcements at http://www.hq.nasa.gov/office/mtpe/
and I only receive a message that "document contains no data".  I
contacted NASA and the response was that the information is there, so
they do not know why I am having a problem.  I was using Netscape; I was,
however, able to find it through Mosaic.