Problem:

You have LaTeX code with a \footnote inside a \tabular like this:

\documentclass{scrartcl}

\begin{document}
\begin{tabular}{p{2cm}|p{2cm}|}
\textbf{Column A\footnote{This is a footnote!}} & \textbf{Column B}\\
1 & 2\\
3 & 4\\
\end{tabular}
\end{document}

but LaTeX/PDFLaTeX is not showing any of the footnotes you declared inside the \tabular environment.

Solution:

Use this code just after your \documentclass declaration:

\usepackage{footnote}
\makesavenoteenv{tabular}

Then recompile your LaTeX code. The footnotes inside your tabular should now appear as expected.

Note that if you are using other environments than \begin{tabular} you might need to add more \makesavenoteenv declarations for the correct environments. The tabularx environment from the tabularx package works with footnotes out-of-the box without any additional packages!

Problem:

You have LaTeX code containing \glqq and/or \grqq like

\documentclass{scrartcl}

\begin{document}
\glqq Test\grqq
\end{document}

but when you try to compile it, you see an error message like this:

! Undefined control sequence.
l.5 \glqq
          Test\grqq
? 

Solution:

In order to use \glqq or \grqq you need to include

\usepackage[ngerman]{babel}

after your \documentclass declaration.

In case you want to use another language, use the correct language specifier instead of ngerman.

Note: This is the recommended method for using € and other symbols in LaTeX!

In order to insert the € symbol into your LaTeX document, first add

\usepackage[official]{eurosym}
\usepackage[utf8x]{inputenc}

to the top of your document, e.g. directly after your \documentclass line.

After that, you can use the normal € symbol anywhere in your document like this:

€

to insert an € symbol.

Note: This method is no longer recommended and only provided for compatibility reasons! See How to insert Euro symbol in LaTeX using UTF8 for the recommended method instead!

In order to insert the € symbol into your LaTeX document, first add

\usepackage[official]{eurosym}

to the top of your document, e.g. directly after your \documentclass line.

After that, you can use

\euro{}

to insert an € symbol anywhere in your document.

To set or reduce the page margin (white space between the border of the page and the text) you can use the geometry package.

Set margin of all sides to 2cm:

\usepackage[left=20mm, right=20mm, top=20mm, bottom=20mm]{geometry}

To set just the left and right margin to 2cm, use

\usepackage[left=20mm, right=20mm]{geometry}

This is a minimal example using the LaTeX booktabs package which you can use & modify to create your own table.

\documentclass{scrartcl}
\usepackage{booktabs}
\usepackage[utf8x]{inputenc}

\begin{document} 

\begin{table}[h!]
    \begin{center}
      \caption{Minimal booktabs example.}
      \label{tab:table1}
      \begin{tabular}{l|c|r}
        \toprule % <-- Toprule here
        \textbf{Column 1} & \textbf{Column 2} & \textbf{Column 3}\\
        $\alpha$ & $\beta$ & $\gamma$ \\
        \midrule % <-- Midrule here
        A & 10.23 & a\\
        B & 45.678 & b\\
        C & 99.987 & c\\
        \bottomrule % <-- Bottomrule here
      \end{tabular}
    \end{center}
  \end{table}
\end{document}

Render it using

pdflatex booktabs.tex

The table looks like this:

Problem:

You want to compile your LaTeX file on Ubuntu using latex or pdflatex but you see an error message like this:

! LaTeX Error: File `siunitx.sty' not found.

Type X to quit or <RETURN> to proceed,
or enter new name. (Default extension: sty)

Solution

sudo apt -y install texlive-science

This will install, among many other LaTeX files, siunitx.sty.