Visual Studio 2015 Add Class, Error: "object already exists"

Question

Other similar but to my knowledge non-related questions:

A file or folder with the name '' already exists Visual Studio 2012

ATL simple object wizard - "Object Xxx already exists" error

The error:
I try to add a simple class and then proceed to the wizard where I get the following Error]2: "Object already exists".
I can't add the class "MainGame" (and a few other names) to any project, not even if I create a new project

How to recreate said bug/error:
The error occured when I deleted a Release folder I'd accidentally copied over from a project in another solution. All now non-functional class names are derived from the object files within that Release folder.

Solution:
I have no solution.

My questions are:
Have anyone else had this or a similar issue?
If so, have you solved it and what is your solution?

I am open to all suggestions and while this 'bug' isn't making programming impossible it is quite annoying not being able to use frequently used class names.

Answer 1

Yeah, also saw that.

I think I have created a C++ class, decided I don’t like it, reverted changes using github app. But the name was good, so I tried creating same class again. Saw the exact same error as you’re having.

The name polluted the sqlite database. And because I had that VC.db in my .gitignore, git hasn't reverted that.

To fix, quit visual studio, delete the file $(SolutionName).VC.db in your $(SolutionDir) folder, restart visual studio, clean and rebuild your project[s].

Update: Modern versions of Visual Studio usually keep these SQLite databases inside .vs folder under $(SolutionDir).

Answer 2

Seems like VS caching issue. I too faced this issue and your solution did not work for me either.

What I did is add a Class with different name lets say MainGame1 and then it allowed me to add. Then I just renamed the Class name, CPP and header file name to my like.

Answer 3

Manually create example.h and example.cpp in Solution directory then:

Add -> Existing Item... -> add created file to your project.

This trick work for me after clean $(SolutionName).VC.db file.