conflicting options errors

Question

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}}
\renewcommand*{\multinamedelim}{\addcomma\space}
\renewcommand*{\finalnamedelim}{\addcomma\space}
\renewbibmacro{in:}{}
\addbibresource{trybib.bib}

\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?

Answer 1

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

• How to use biber
• biber .bcf file extension
• utf8 or latin1 input encoding?
• change encoding of files
• Which packages to load after hyperref?
• What packages do people load by default?
• lmodern vs. cm-super
• font packages

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

\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}}
\renewcommand*{\multinamedelim}{\addcomma\space}
\renewcommand*{\finalnamedelim}{\addcomma\space}
\renewbibmacro{in:}{}
\addbibresource{biblatex-examples.bib}

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

\begin{document}
Lorem ipsum, dolor sit amet \cite{kastenholz}.
At vero utilisam \cite{bertram}.
\printbibliography
\end{document}