Are you encountering the 'Could not copy obj debug netcoreapp2 to bin debug' error in Visual Studio? This error can be frustrating, but don't worry, we've got you covered with some solutions. Here's what you can do to resolve this issue:

1. Clean and rebuild your solution: Sometimes, the error can be fixed by simply cleaning the solution and then rebuilding it. This can help resolve any build errors that may be causing the problem.

2. Check for file locks: The error may be occurring due to file locks on the debug folder. Make sure to check for any processes that may be locking the files and release them before attempting to copy the files again.

3. Update your packages: Make sure that all the packages and dependencies in your project are up to date. Sometimes, outdated packages can cause build errors and lead to the 'Could not copy obj debug netcoreapp2 to bin debug' error.

4. Permissions issue: Check if the user account running Visual Studio has sufficient permissions to perform the file copy operation. You may need to run Visual Studio as an administrator to resolve this issue.

5. Check for errors in the output window: The output window in Visual Studio can provide valuable information about what exactly is causing the error. Check the output window for any specific error messages that can help you pinpoint the issue.

By following these steps, you should be able to troubleshoot and resolve the 'Could not copy obj debug netcoreapp2 to bin debug' error in Visual Studio. Remember to always keep your development environment and dependencies up to date for a smoother development experience.