I want to draw the following table in LaTeX. In the first column the text should be left aligned. The text in all other cells should be centered. The first problem occurs with D in the first row. If I write a \centering in front of D, I get a LaTeX error. The second problem is, that I want to vertically align the text in all cells but I don't know how. I have found a solution but it doesn't work if the width of the first column is specified.
\documentclass{article}
\usepackage{blindtext}
\usepackage{tabularx}
\begin{document}
\begin{tabularx}{\textwidth}{|p{4cm}|X|X|X|X|}
\hline
& \centering A & \centering B & \centering C & D\\
\hline
\blindtext & 123 & 123 & 123 & 123\\
\hline
\end{tabularx}
\end{document}

\arraybackslashto\centeringor use\tabularnewlineinstead of\\. – Qrrbrbirlbel Apr 13 '13 at 00:55