Perl CSV reading characters that aren't there - csv

Question

I'm reading in a file using Perl's Text::CSV_XS package which I am reading on Ubuntu:
open my $fh, '<:encoding(utf8)', 'file.csv' or die "Can't read csv: $!"; # error shows on this line
while (my $row = $list->getline ($fh)) {
....
}
and this reads just fine until one line gives an error:
UTF-8 "\xE9" does not map to Unicode at 0.xlsx_to_json.pl line 198, <$_[...]> line 14019.
looking online, this suggests that this is a ê character or something similar, which is strange because I don't see any such characters on line 14109, that line looks just like any other line.
I tried changing the open line to
open my $fh, '<', 'file.csv'
but that gives the same error.
I tried opening the CSV and saving as CSV with a different delimiter, but I can't do that in Excel 2016 anymore, the option to change the delimiter simply doesn't appear
I tried opening in LibreOffice to save as a CSV, but an update removed the ability to change the delimiter
How can I read this CSV file without this strange error?

Answer 1

Your file is not a valid UTF-8 file. Byte E9 appears where it's not expected.
Followed by two continuation bytes = ok
$ perl -M5.010 -MEncode=decode -e'
decode("UTF-8", "\xE9\xBF\xBF", Encode::FB_WARN | Encode::LEAVE_SRC);
say "done";
'
done
Not followed by two continuation bytes = bad
$ perl -M5.010 -MEncode=decode -e'
decode("UTF-8", "\xE9\x41", Encode::FB_WARN | Encode::LEAVE_SRC);
say "done";
'
UTF-8 "\xE9" does not map to Unicode at -e line 2.
done
Fix your bad data.