Hi,

You mean how do you rename a project? The solution simply contains a number of projects and can be anywhere and called anything.

The shortest way is to right click the main .ino sketch file in the solution explorer and use the Visual Micro rename option.

However so you can fix or manually rename here is some info:-

To rename a project you have to follow the Arduino rules. Keep in mind that Arduino only knows of the folder name and a matching .ino of same name. 

So that's the first rule, the .ino has to be the same name as the sketch folder that contains it.

ie: Blink.ino in the Blink folder

Visual Micro also expects the Visual Studio project name to be the same as the folder and [sketch_name].ino. In Visual Studio the project has a few project files but also an internal name displayed (and renamed) in the solution explorer. You should keep both the internal and external project names the same.

Blink project name
Blink.vcproj etc...

Finally, if you manually change the name of the sketch and want to retain any additional Visual Micro project properties that you have applied (such as debug or compiler settings) you should also rename the xml files in the .Visual Micro sub folder. Otherwise the files will be created with new names for the newly named project. In that case you would be using the defaults.

Alternatively delete the Visual Studio files in the sketch folder (not any source code) and the files in the .Visual Micro folder and re-open using the Visual Micro "File>Open>Sketch Project". In that case Visual Micro will create a new Visual Studio project and configure all the sources for you.