Visual Studio 2015 - "Unable to step. The operation could not be completed. A retry should be performed"

I've also ran into this issue before in Visual Studio 2015 Update 3 on Windows 7 SP1 (64-bit).

Try disabling the Visual Studio hosting process.
Project Properties > Debug > uncheck "Enable the Visual Studio hosting process"

Also, are you running out of memory?

Are you debugging an ASP.NET website?

A known issue with the Visual Studio debugger causing this problem. There is a race condition that happens when all of the following are true:

1. Script debugging is enabled in IE
2. User is debugging IE and another process
3. The other process stops (hits breakpoint, step operation completes, stops at an exception, etc) at a moment when IE is not running script code
4. IE starts running script code at roughly the same moment that the user hits F10/F5 in Visual Studio. The most likely reason for this to happen is that the code from ‘setTimeout’ is run – there could be other reasons as well.

Workaround

1. If you hit this problem, you can try detaching and reattaching the debugger.

   -or-

2. This problem happens when debugging ASP.NET and when script debugging is enabled in IE. If you disable script debugging in IE, or toggle it on and off when switching between debugger server-side and client-side problems, you would be able to work around the issue.

   -or-

3. If your web application is using setTimeout, you may be able to avoid or at least reduce the problem by doing something to ensure that script runs less often. This could mean increasing the timeout value, or this could mean adding conditions around when setTimeout is used.

Sources:

• https://blogs.msdn.microsoft.com/rakkimk/2008/06/07/getting-unable-to-step-the-operation-could-not-be-completed-a-retry-should-be-performed-while-debugging-in-visual-studio/
• https://blogs.iis.net/rakkimk/getting-quot-unable-to-step-the-operation-could-not-be-completed-a-retry-should-be-performed-quot-while-debugging-in-visual-studio
• https://social.msdn.microsoft.com/Forums/vstudio/en-US/2320a943-d52d-437a-abec-6f1e9f929b52/debugger-error-unable-to-step-the-operation-could-not-be-completed?forum=vsdebug

Are you debugging a Universal Windows App?

If so, a work-around could be to reinstall "Tools for Universal Windows Appps Development" as follows:

· If the “Tools for Universal Windows Apps Development” are still installed:

1. Go to Programs and Features, select Visual Studio 2105, click Change.

2. In Visual Studio setup, click Modify.

3. Deselect the feature “Tools for Universal Windows App Development”

4. Select “Tools for Universal Windows App Development” again, and click Update.

· If you have already uninstalled the “Tools for Universal Windows Apps Development”:

· Reinstall “Tools for Universal Windows App Development”

· Or, take the following steps to reinstall the JavaScript project system and language service:

§ Download the installer for your edition of Visual Studio, e.g., vs_community.exe.

§ Open a CMD window, and run the following command: vs_community.exe /modify /installselectableitems JavaScript_Hidden /passive

Source: - https://social.msdn.microsoft.com/Forums/vstudio/en-US/c9936d80-087d-4cad-93bf-ca4873889773/the-debugger-cannot-continue-running-the-process?forum=vsdebug

In Visual Studio 2015, 2017 and 2019 you can do that:

Go to Tools -> Options -> Debugging -> General

Turn off

"Break all processes when one process breaks"

Solved it by completely uninstalling Visual Studio and ReSharper. I used this tool:

https://github.com/Microsoft/VisualStudioUninstaller

After re-install everything worked again.