how do I combine two PDF files, using OS X 10.8.2? I've tried following other suggestions such as open PDF, open thumbnails, drop and drag it. It won't let me drop and drag. When I go into security settings I can see Document Assembly and Page extraction are not allowed. Is this the problem? I just really need to combine these two PDF files
Open first PDF in Preview.app. Use the view menu to enable thumbnails.
Back in Finder, drag and drop the second PDF file into the Preview thumbnail gallery below the first document. Save.
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