documents and settings/jacques/daz3d/studio4/my library/content is almost certainly wrong, it's the DS3 default name nested inside the DS4 default name. Most likely you don't need the Content folder there, and should copy the contents out and paste them into the My Library folder - but check the settings for content paths in Edit>Preferences>Content Library>Content Directory Manager. I don't recommend using the search function, it's too likely to grab folders it shouldn't - especially if there are installation issues already.