Read a UTF-8 text file with BOM
Have you tried read.csv(..., fileEncoding = "UTF-8-BOM")?. ?file says:
As from R 3.0.0 the encoding ‘"UTF-8-BOM"’ is accepted and will remove a Byte Order Mark if present (which it often is for files and webpages generated by Microsoft applications).
This was handled between versions 1.9.6 and 1.9.8 with this commit; update your data.table installation to fix this.
Once done, you can just use fread:
fread("file_name.csv")