I am getting the following error while compiling my Latex File :

! LaTeX Error: Cannot determine size of graphic in tree.jpg (no BoundingBox).

Why do I get this error ? What has this to do with an .eps file ?

Infact, I could compile it fine with MacTex on my machine. But when I submit it online to a scientific journal for publication, it compiles it on the server and sends me the resultant PDF which as all these error that prevent it from compiling.

I am using the following syntax for including the images :

\begin{figure}[!h]
    \begin{center}
        \scalebox{0.45}{
            \includegraphics{tree.jpg}}
    \end{center}
            \caption{\small A sample}
            \label{tree}
\end{figure}

What should I do ? Could it be that their server is using an old compiler ?

UPDATE : It finally worked. I converted the first image to PDF and the compilation happened perfectly. I guess it used the bounding box value from that PDF and applied it to all images.