Relative path to XSD

I'm reference an XSD in the project directory tree from an XML file. When I put the XSD in the same directory as the XML file, both "on-the-fly" validation and "full" validation work. If I put the XSD in a different directory than the XML file, "on-the-fly" validation continues to work, but the "full" validation gives me an error.

Here's the reference to the XSD in the XML file: xsi:noNamespaceSchemaLocation="../common/ctap.xsd"

The XML file is here: C:\Users\dafink\Documents\Project_files\version2\1.5.0.1\embeddedFavoriteSettingsFavorite.xml

The XSD file is here: C:\Users\dafink\Documents\Project_files\version2\common\ctap,xsd

Here's the error I get:

Error:External resource file:///C:/Program%20Files%20(x86)/JetBrains/WebStorm%2011.0.3/jre/jre/common/ctap.xsd is not registered
C:\Users\dafink\Documents\Project_files\version2\1.5.0.1\embeddedFavoriteSettingsFavorite.xml
Error:Premature end of file.

What am I doing wrong?