The first thing that you need to do is to set the Page Size. By default it is set to 0 which means, that paging is disabled. The other thing that you have to do is to modify the XSL so that the Content Query Web Part becomes aware of paging and will be able to display the paging controls.
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The support for paging in Content Query Web Part requires changes to two XSL files used by the CQWP: the ContentQueryMain.xsl and ItemStyle.xsl. The first configures the parameters and passes information to the Item Templates that is required in order to display the paging controls. The ItemStyle.xsl is responsible for displaying the pager control. Depending on your scenario you might either want to create a different paging control for every template or create a single one and reuse it across all templates.
To see it all working you can download the examples of the XSL files that enable paging. Simply upload them to your Site Collection and change the links in the properties of the Imtech Content Query Web Part.
Imtech Content Query Web Part is a free Web Part and you can use it without any restrictions. Please note, that it is not supported by Microsoft and you use it at your own risk.
Download: ImtechContentQueryWebPart.wsp (7KB, WSP) Download: ImtechContentQueryMain.xsl (19KB, XSL) Download: ImtechItemStyle.xsl (32KB, XSL)
And if you are interested how it all really works stay tuned for the Imtech Content Query Web Part How they do it article!
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