Mac compatible issue, Other issue raised

Yesterday, when I was just resumed my Echo programming project and just added some classes into the programming and after that my, MAC behaving differently. There is an error called itunes error 0xe8000015 to arise and when I remove those classes, the error gets solved. Does it make any sense? I don’t understand why this happens? I tried to resolve it but I don’t understand that why this issue arised what’s the solution of it?