Subfigures not working

Question

I'm trying to place two figures side by side using subfigure and I'm getting not being able to compile the file to pdf. The error goes away once the commands for this environment are commented out (i.e. \begin{subfigure}[t]{0.3\textwidth} and \end{subfigure}) but then obviously the figures get placed one after the other. Please point out the mistakes in the code, if there are any, or an alternative solution to this.

The error message: !pdfTeX error: pdflatex (file ecrm1095): Font ecrm1095 at 600 not found ==> Fatal error occurred, no output PDF file produced!

Also, consider the fact that the subcaption package that I use for the subfigure was recently separately installed by me to the TexLive.

\documentclass[a4paper,12pt,twoside]{report}
\usepackage{amssymb,amstext,amsmath,hyperref,graphics}
\usepackage[T1]{fontenc}
\usepackage{epstopdf}
\usepackage{caption}
\usepackage{subcaption}
\usepackage{hyperref}
\hypersetup{
colorlinks=true,
pdfborder={0 0 0},
citecolor= blue,
linkcolor= black,
}
    \ifx\pdfoutput\undefined
    \usepackage{graphicx}
    \else
    \usepackage[pdftex]{graphicx}
    \fi
\setlength{\parskip}{0.8em}

\begin{document}

Hello World and the \it Master of Dreams!

\begin{figure}
\begin{subfigure}[t]{0.3\textwidth}
    \includegraphics[width=\linewidth]{energyplot_dt_compare}
    \caption{enrgy}
    \label{fig:E_deltat}
\end{subfigure}
\begin{subfigure}[t]{0.3\textwidth}
    \includegraphics[width=\linewidth]{energy_typical_lj}
    \caption{Energy plot of the system at T=1}
    \label{fig:typicalE}
\end{subfigure}
\end{figure}

\end{document}

Update: Taking cue from the question: [Font installed, compiles to dvi, but fails compiling to pdf. "font at 600 not found", i tried to compile directly to dvi instead of compiling to pdf (which is what I was doing before) and it compiled! But it still wouldn't compile to pdf. I tried the soultion in the question mentioned but it is not working either.

Update 2: Even though I have not found any satisfactory answer yet I found a way around, which is to not use the fontenc, instead use some package like lmodern. I owe this solution to cfr. Please refer to the answer by cfr: https://tex.stackexchange.com/a/205197/99160