Outlook add-in with Visual Studio 2013 not works

I created a small add-in outlook project with visual studio 2013. When I run the add-in for the 1st time, it works. But if I start outlook and that I remove this add-in, when I want to launch it again from visual studio to debug for example, the add-in is no more taken into account by outlook. What does do to solve this problem?

If you created a VSTO based add-in you just need to build it to get it registered anew.
Typically the windows registry keys allow to detect what add-ins are registered and then load them. Read more about the required windows registry keys in the Registry Entries for Application-Level Add-Ins article.