move application from exchange server 2007 to 2013 and 2016

Question

??

Dear Friends,

I have to work on one email application which has developed on visiual studio 2005

 and working with Exchange server 2007.

 

now i have to custmise that mailing application so that that application can run onto exchange server 2013 and 2016

  they are using AD for storing data and fatching mail address and all data from AD to send mail 

 

Code has developed in asp.net and C#. in vs 2005 version.

 

what to do for that?

 

 should i use upgraded version of visiual studio like 2013 and run and build that code accourding to that (if so that then how to migrate that code in higher version)?

or any other option to do any changes in code to run onto exchange server 2013 and 2016??

 

i have never worked before on this type of project and vs2005 earlier ,

please help me