Hi,
by chance I have the solution for this in my code sample at Avoiding Strange Win32::ODBC Return Values for Integers (NUL).
Look at the parts 
#  Add and define a format
my $header = $workbook->addformat(); # Add a format
...
$header->set_bg_color('yellow');
...
$worksheet->write($row, $col++, $_, $header) for @fields;

[download]
Cheers,
jonix

In reply to Re: Changing the background color of an excel cell by jonix
in thread Changing the background color of an excel cell by mike5091231

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