Problems in Generating the Reference List with TexMaker

Problems in Generating the Reference List with TexMaker

I have my .tex file as follows:
\documentclass[12pt]{article}
\usepackage{natbib} % for the bibliography
\begin{document}
A much longer \LaTeXe{} example was written by Gil~\cite{label1}.
\bibliographystyle{unsrt}
\newpage \bibliography{Weekly Report 10}
\end{document}
My Weekly Report 10.bib file is as follows:
@InProceedings{label1,
author = {author},
title = {title},
booktitle = {booktitle},
OPTcrossref = {OPTcrossref},
OPTkey = {OPTkey},
OPTpages = {OPTpages},
OPTyear = {OPTyear},
OPTeditor = {OPTeditor},
OPTvolume = {OPTvolume},
OPTnumber = {OPTnumber},
OPTseries = {OPTseries},
OPTaddress = {OPTaddress},
OPTmonth = {OPTmonth},
OPTorganization = {OPTorganization},
OPTpublisher = {OPTpublisher},
OPTnote = {OPTnote},
OPTannote = {OPTannote}
}
I have them together in one folder.
I have also run PDFLaTeX first, and then BibTeX, and then PDFLaTeX twice
more.
However, my reference list is always empty. The error messages are as
follows:

Where goes wrong?