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The custom style sheet property of the site has been removed in 2010. &nbsp;You have to create a custom master page with it attached. &nbsp;This can be done very easily with SharePoint designer. &nbsp;just copy the OOB one you use and add the link.
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Because that's the solution.
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I need to attach a custom CSS that all sites in a site collection can use it. I <b>don't</b> have publishing features enabled. Where do I save that CSS file and how do I properly attach it?
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I need to attach a custom CSS that all sites in a site collection can use it. I don't have publishing features enabled. Where do I save that CSS file and how do I properly attach it?

The custom style sheet property of the site has been removed in 2010.  You have to create a custom master page with it attached.  This can be done very easily with SharePoint designer.  just copy the OOB one you use and add the link.

How to attach CSS file in Sharepoint 2010

I need to attach a custom CSS that all sites in a site collection can use it. I don&amp;#39;t have publishing features enabled. Where do I save that CSS file and how do I properly attach it?

Microsoft Sharepoint is a software platform and family of software products used for collaboration and web publishing combined. These capabilities include developing web sites, portals, intranets, content management systems, search engines, wikis, blogs, and other tools for business intelligence and collaboration. SharePoint has a Microsoft Office-like interface, and it is closely integrated with the Office suite.