Problem: Unity Keeps Opening Visual Studio

Problem

Every time I open C# script in Unity, it keeps opening new instances of Visual Studio rather than in existing one.

Version

• Unity 2017.1.1p3 (64-bit)

Solution

Delete Visual Studio’s solution file (*.sln) and project file (*.csproj). Let Unity generate these files again.

This problem seems more likely to happen after upgrading the project to the new version of Unity.

Reference

• Unity keeps opening new instances of Microsoft Visual Studio - Unity Answers