Force table column widths to always be fixed regardless of contents

Make the table rock solid BEFORE the css. Figure your width of the table, then use a 'controlling' row whereby each td has an explicit width, all of which add up to the width in the table tag.

Having to do hundreds html emails to work everywhere, using the correct HTML first, then styling w/css will work around many issues in all IE's, webkit's and mozillas.

so:

<table width="300" cellspacing="0" cellpadding="0">
  <tr>
    <td width="50"></td>
    <td width="100"></td>
    <td width="150"></td>
  </tr>
  <tr>
    <td>your stuff</td>
    <td>your stuff</td>
    <td>your stuff</td>
  </tr>
</table>

Will keep a table at 300px wide. Watch images that are larger than the width by extremes

Specify the width of the table:

table
{
    table-layout: fixed;
    width: 100px;
}

See jsFiddle

Try looking into the following CSS:

word-wrap:break-word;

Web browsers should not break-up "words" by default so what you are experiencing is normal behaviour of a browser. However you can override this with the word-wrap CSS directive.

You would need to set a width on the overall table then a width on the columns. "width:100%;" should also be OK depending on your requirements.

Using word-wrap may not be what you want however it is useful for showing all of the data without deforming the layout.