duplicate 'row.names' are not allowed

I am getting an error when trying to import tab delimited .txt file saved
from Excel.
I have read what is posted on the forums but still am confused.

I saved my Excel file (DataTestforR.xlsx) as a tab delimited txt file
(DataTestR.txt) on my Desktop.
In the RGUI, I tried to import the txt file and got an error

myfile<-"C:\\Users\\jpapa\\Desktop\\DataTestR.txt"
mydf<-read.delim(myfile, header=TRUE,sep=" ", dec=".")

Error in read.table(file = file, header = header, sep = sep, quote =
quote,  :
 duplicate 'row.names' are not allowed

The first row of my file has column names and the first column of my file
has unique identifing names (not duplicated):
Cu Sa Na Ci Se NM NPI IPI Seg
0090.00 15.48 1 SOM S L TX 0 0.2 0.2 7-Very