This is a problem because when I do email campaign, There is a link on the email, that link to my company homepage, I would like to differentiate between the visitor come from another way (e.g. search on google) or the visitor come from the email I have sent.
Notice that they should come form a email instead of a website,
Is it able to check such kind of information ? And is it possible to differentiate between campaign 1 and campagin 2 with same link? Thankyou
You cannot differentiate between an email vs web campaign link unless that link is tagged for campaign tracking. Campaign link tracking requires that you append additional data to the query params of a link according to specific conventions required by GA in order to differentiate between different campaigns.
Other wise, Google Analytics would not be able to differentiate between the same links from email vs banner links on a very granular level.
http://support.google.com/googleanalytics/bin/answer.py?hl=en&answer=55540