Error using conversion from raster to polygon

[AndrewKuder]

Just getting back into GIS after being out of the game for a few years and I was wondering if anyone has any suggestions on why I am having trouble converting a raster image to a polygon in ArcGIS 10?  I downloaded the data from PASDA, a Pennsylvania clearinghouse run through Penn State, and it displays fine however I keep getting an unknown error message (ERROR 999999) when I try to run the geoprocessing tool to convert it from a raster image to a polygon.  Do I have to change the type of raster extension to get a better result, such as changing from .img to .tiff?  Also does cell size affect the outcome of the conversion?  Any help would be appreciated.

[SimonKettle]

In my experience the raster to polygon tool works best using a TIFF file also ERROR 999999 sometimes means insufficent memory so try cutting the size of the raster.

But you can us any valid integer raster dataset, so the cells represent discrete data not floating point raster data...and have any cell size. Just make sure you use appropriate tool...when you convert to ASCII are the raster numbers decimals (floating raster) or whole integer (discrete data raster)?

http://webhelp.esri.com/arcgiSDEsktop/9.1/index.cfm?TopicName=Floating%20point%20and%20integer%20dat...

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Raster_to_Polygon/001200000008000000/