[R] Error opening SHP file (maptools)

[gerickes at earthlink.net]

I am having difficulty loading a points shapefile (1600 records) I generated from ArcGIS as a PointsSpatialDataFrame using the maptools readShapePoints function.

library(maptools)
surveypts <- readShapePoints(system.file("C:/temp/survey.shp", package="maptools")[1]
Error in getinfo.shape(filen) : Error opening SHP file

I've tried numerous re-exports and renames of the dataset, to no avail. I've also tried placing the shapefile in the library's shapefile folder, with the example dataset (see example below). 

x <- readShapePoints(system.file("shapes/survey.shp", package="maptools")[1]

No luck there either. I'm quite new to R, but I can follow a manual and google well enough. However, I haven't seen anything to help me. The example point datasets load fine. I figure that I'm missing on some familiarity with R and that I don't know the tricks yet. Any help?

Thanks in advance.

Gericke Cook
USDA-APHIS-PPQ