Data sites must be distinct error when changes are made in .csv file.

I am trying to use the spline function in matlab but I get the error, "data sites must be distinct" when the function is executing. The data is being read from a csv file. I have realized that this has nothing to do with the function itself as making no changes to the data in the csv file and just simply saving it also results in that error. However, that error does not occur when I make changes in notepad. Is there a way around this because I have around 1000 rows of data and cant afford to make changes in notepad and would like to paste in csv. Thanks

[Walter Roberson]

Which program are you using to make the changes in the .csv file that give you this error ?