I downloaded a sample project from the web and of course, this project has a different target deployment server then my SharePoint server.
I could find hundreds of articles about packaging etc etc but none told me where to change this setting. (No, it's not changeable in the OBVIOUS right mouse on project ->properties ->"SharePoint" screen...!
After getting frustrated finding nothing interesting on the web I tried fixing it myself; opening up the .csproj file with notepad myself... tadaa..!! Fourth line:
YES ! Let's try to change that... Voilà !! Happiness :D :D
(Quickly write a handy blog about this !)