Looking at one of my MAP files, I have...
At the beginning I have a SHAPEPATH defined which will be relative to the directory your MAP file is in...
# On Windows systems, /tmp and /tmp/ms_tmp/ should be created at the root
# of the drive where the .MAP file resides.
and further down for the layer definition this is going to be the name of the shapefile without the path because the SHAPEPATH above already sets that up...
Notice that the DATA def has no quotes. At the very least, try removing the quotes first. Failing that try setting the SHAPEPATH and make sure your IMAGEPATH and IMAGEURL are resolvable URL because these are the location for the temp images MapServer creates accessible to your web app.
Edited by blindthief on 05/24/07 06:56 AM.