Every notice contains a case number, and that case number should be a hyperlink.  If the case number is not a hyperlink, it may be that your security settings in your email are removing the hyperlinks. 

If the case number in your notice is a hyperlink and there is a document number that is not a hyperlink, then there is not a PDF document for that entry.  This may happen for some entries where the judge wanted the entry to have a number but there is not a PDF file associated with the entry.  An Oral Order would be an example of this type of entry.