# Problem with \multicolumn in \longtabu environment

I'm a relative newbie to LaTeX and am having a problem with a longtabu table. I've set it up with alternating row colors, which works great. However, this makes the captions on all but the first page the alternate color. To get around this I tried a \multicolumn row in the header as shown in the MWE below. I also included a \multicolumn row in the footer with the same results.

\documentclass[12pt]{article}
\usepackage{geometry}
\usepackage{graphicx}
\usepackage{tabu,xcolor,colortbl}
\usepackage{caption}
\usepackage{array}
urlcolor  = blue,
citecolor = blue,
anchorcolor = blue]{hyperref}
\usepackage{longtable}

\begin{document}

\taburowcolors[2]{white .. blue!20}

\tabulinesep=6pt
\arrayrulewidth=1pt

\begin{longtabu}[h]{| m{1.75in} | m{1.5in} | m{2.75in} |}

\caption{This is the first page header} \label{Table:example}\\
\rowcolor{blue}\color{white}Column 1  & \color{white}Column 2 & \color{white}Column 3\\

\rowcolor{white}\multicolumn{3}{c}{Table~\ref{Table:example}: Continued from previous page}\\
%\caption{Continued from previous page}\\
\rowcolor{blue}\color{white}Column 1  & \color{white}Column 2 & \color{white}Column 3\\

\hline
%\rowcolor{white} \multicolumn{3}{l}{Continued on next page}\\

\endfoot

\hline
\endlastfoot

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

This is Column 1 & This column describes Column 1 and is generally a little longer &  This is a longer description that will take up a few lines of text in the table. It is really just a bunch of text. This really means nothing in this minimum working example other than to take up space in the table.\\

\end{longtabu}

\end{document}


This works but throws a couple of Misplaced\omit \end{longtabu}

errors and a bunch of overfull and underfull \hbox as shown below.

line 66: Misplaced \omit \end{longtabu}
line 66: Misplaced \omit \end{longtabu}
line 66: Overfull \hbox (43.61536pt too wide) in alignment
line 66: Overfull \hbox (43.61536pt too wide) in alignment
line 66: Overfull \hbox (43.61536pt too wide) in alignment
line 66: Overfull \hbox (43.61536pt too wide) in alignment
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 10000) in paragraph
line 66: Underfull \hbox (badness 2837) in paragraph
line 66: Overfull \hbox (43.61536pt too wide) in alignment


Is there something that I can do to get rid of the errors?

Thanks

Use \cellcolor, not \rowcolor:

\begin{longtabu}{| >{\raggedright}m{1.75in} | >{\raggedright}m{1.5in} | >{\raggedright\arraybackslash}m{2.75i\$

\caption{This is the first page header} \label{Table:example}\\
\rowcolor{blue}\color{white}Column 1  & \color{white}Column 2 & \color{white}Column 3\\

I set a small margin just to avoid the table overshooting the width. With \raggedright the cells don't throw tens of Underfull \hbox warnings.