As per this link:
http://www.databasedev.co.uk/alternate_rows_2007.htmlTo apply alternate row colours in the Access 2007 report, we can do this in various ways.
1. If we go to design view of the report and select the Detail section, we can then view the format properties for this section. Here we can specify an Alternate Back Color to be used. We can also set the Back Color for the detail section.
2. We can also specify these settings using the Report Layout Tools, and the Format contextual tab. Here we can select a Row in Layout view, and specify the Alternate Row Color from the Font tools:
if the first method does not work, try the second method.