I have a very large dataset (70k rows, 2600 columns, CSV format) that I have created by web scraping. Unfortunately, doing the pre-processing, processing etc. at some point
Not sure it will work for you but for the same symptoms i did convert the strings to ascii:
x <- iconv(x, "", "ASCII", "byte")
For non ascii chars, the indication is "" with the hex code of the byte.
""
You can then gsub the hex codes to the values that suit you.