Shape file problem

#in my shape file, column names have come
#SD_csv_O,  SD_CSV_D,instead of open water,
#or other names like that because of my problem in creating shape file.

Well, we don't know how you created the shapefile so we can't solve
that problem.

# I wanted to assign the correct names of my columns using names (data).
But got error
colnames(data) <- c( "STATEFP","COUNTYFP","COUNTYNS" ,  "GEOID",
"NAME","NAMELSAD","LSAD","CLASSFP","MTFCC","CSAFP","CBSAFP","METDIVFP","FUNCSTAT","ALAND","AWATER","INTPTLAT","INTPTLON",
"Openwater","Dev
open","DevLowin","DevMed","DevHi","Barren","Deciduous","Evergr","Mixfor","Shrub","Grass","Sedge","Cultcrop","Woody","wetHerb","p2010","Areasqml","Popsqm")

Error in `colnames<-`(`*tmp*`, value = c("STATEFP", "COUNTYFP", "COUNTYNS",

Why did you say "using names (data)" and then try "colnames(data)"?
Because "names(data)" should work. Here is a complete reusable
example:

 > require(sp)

 > data=data.frame(x=runif(10),y=runif(10),z1=runif(10),z2=runif(10))
 > coordinates(data)=~x+y
 > data
            coordinates         z1         z2
1  (0.724746, 0.557815) 0.47356654 0.93721636
2   (0.614448, 0.10798) 0.80956133 0.78836015
3   (0.39065, 0.845377) 0.61940167 0.36847489
4   (0.35598, 0.363572) 0.07214902 0.45609632
5  (0.248248, 0.219995) 0.64276010 0.52574029
...

 > colnames(data)
NULL
 > names(data)
[1] "z1" "z2"
 > colnames(data)=c("foo","bar")
Error in `colnames<-`(`*tmp*`, value = c("foo", "bar")) :
  'dimnames' applied to non-array
 > names(data)=c("foo","bar")
 > data
            coordinates        foo        bar
1  (0.724746, 0.557815) 0.47356654 0.93721636
2   (0.614448, 0.10798) 0.80956133 0.78836015
3   (0.39065, 0.845377) 0.61940167 0.36847489
4   (0.35598, 0.363572) 0.07214902 0.45609632
5  (0.248248, 0.219995) 0.64276010 0.52574029
6  (0.955221, 0.185988) 0.93994016 0.64672931
...