# conflicting options errors

I have in the preamble:

\documentclass{article}
\usepackage{amssymb,amstext,amsmath,latexsym,mathtools}
\usepackage[italian,british]{babel}
\usepackage{pdfpages}
\usepackage[utf8,latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{csquotes}
\usepackage{cmbright}
\usepackage{setspace}
\usepackage{pdfpages}
\usepackage{hyperref}
\usepackage[style=authoryearcomp,firstinits=true,maxcitenames=2,maxbibnames=99]{biblatex}
\DeclareNameAlias{sortname}{last-first}
\DeclareFieldFormat[article,periodical]{volume}{\mkbibbold{#1}}
\renewbibmacro{in:}{}

\nocite{*}


I get these two errors:

conflicting options
'firstinits' conflicts with'uniquename=true'


and

Data encoding is 'latin1'
Use backend=bibtex8 or backend=biber


I need all these packages, how can I fix these errors?

-
i dont think you can use two input encoding latin1 and utf8. \usepackage[style=authoryearcomp,firstinits=true,maxcitenames=2,maxbibnames=99]{‌​} , there is closing square bracket ']' missing probably. –  texenthusiast Jun 26 '12 at 18:16
@texlearner A tip: You can use backticks  to mark your inline code in comments as well as in posts. –  doncherry Jun 26 '12 at 18:18
@texlearner: Also, inputenc is for the input encoding (of your .tex file), fontenc would be for the font encoding. –  doncherry Jun 26 '12 at 18:19
@texlearner I have the same problem if I use just either 'latin1' or 'utf8'. I have to fix the options; I am trying to know how –  Aya Jun 26 '12 at 18:33

I just had to do some sorting and cleaning up,
the following questions are probably relevant for you:

After that, I only had to do what biblatex was suggesting.
The following should compile without warnings/errors.

\documentclass{article}
\usepackage{amssymb,amstext,amsmath,latexsym,mathtools}  % do you really need all?
\usepackage{pdfpages}  % you had that package twice
\usepackage{setspace}

\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}  % use utf8 for all files
\usepackage[italian,british]{babel}
\usepackage{cmbright}  % needs the cm-super package to be installed
% \usepackage{lmodern}  % try this one instead of cm-bright + cm-super

\usepackage[autostyle]{csquotes}
\usepackage[
backend=biber,  % run biber.exe instead of bibtex.exe
style=authoryear-comp,
firstinits=true,
uniquename=init,  % this option is compatible with firstinits
maxcitenames=2,
maxbibnames=99
]{biblatex}
\DeclareNameAlias{sortname}{last-first}
\DeclareFieldFormat[article,periodical]{volume}{\mkbibbold{#1}}
\renewbibmacro{in:}{}

\usepackage{hyperref}  % hyperref should usually be the last package
\hypersetup{

biber actually operates on the .bcf` file, so you should use that file extension or, even better, just use no file extension at all. –  matth Jun 27 '12 at 7:25