coverage.xml file empty

coverage.xml file empty

hello,

I use NCover 1.5.7 with command :
% NCover.Console.exe nunit-console.exe TestXXX
(TestXXX.dll)

but it generate an empty file. I don't understand. Tests are executed but the file Coverage.Xml contains :

<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet href="coverage.xsl" type="text/xsl"?>
<!-- saved from url=(0022)http://www.ncover.org/ -->
<coverage />

I read the FAQ for this problem, I don't know what is build symbol files (.pdbs)  ??

thanks

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