I ported my thesis project from overleaf to texmaker. I am working with basic-miktex-2.9.5105 and Texmaker 4.4.1 for Windows. After installing all the packages and it compiled correctly. However, for \ref and \cite I get:

In my document, the libary should be shown as following:
...
\backmatter
\bibliographystyle{siam}
\refstepcounter{chapter}
\bibliography{thesisbiblio}
\clearemptydoublepage
\end{document}
The bibtex file is on the right path and also specified under the right name.

However, on overleaf this worked. I tried to refresh the bibliography under Edit>Refresh Bibliography, however, this does not work.
I really appreciate your replies!