tiff files not displaying

[Matt Garrish]

If anyone could enlighten me as to what I'm doing wrong I would really appreciate it. I'm just trying to get a tiff file to display (Windows XP, IIS 5), but all I get returned is a blank image. The mapserver configuration info is as follows:

MapServer version 4.7 OUTPUT=GIF OUTPUT=PNG OUTPUT=JPEG OUTPUT=WBMP 
OUTPUT=SVG SUPPORTS=PROJ SUPPORTS=FREETYPE SUPPORTS=WMS_SERVER 
SUPPORTS=WMS_CLIENT SUPPORTS=WFS_SERVER SUPPORTS=WFS_CLIENT 
SUPPORTS=WCS_SERVER SUPPORTS=FASTCGI SUPPORTS=THREADS INPUT=POSTGIS 
INPUT=OGR INPUT=GDAL INPUT=SHAPEFILE DEBUG=MSDEBUG

My map file is set up like so:

MAP

  EXTENT -141 42 -52 83
  UNITS DD
	
  SHAPEPATH "data"
  SIZE 300 300
  IMAGETYPE png
   
   LAYER
   	NAME RDATA
   	STATUS DEFAULT
   	TYPE RASTER
	DATA "1KM_RAD.TIF"
   END
END

And I have a wld file in the data directory with the same name as the tif containing the following info:

1000
0.00000
0.00000
-1000
-2750000.131
3000000.244

Do I need to recompile Mapserver with tiff support? Is my problem somewhere else? Any insights would be greatly appreciated!

Matt