Cannot debug tests using Resharper - Cannot Launch Debugger

Question

I'm not able to debug my tests using Resharper-Debug option in my project. I have seen this issue raised by lots of people, but has't come across a solid suggestion which solves my issue. The strange thing is that, if I create a sample project and write a simple unit test, I'm able to debug it without any issues.However when I try to do this in my current project, it simply throws a dialog box saying "Cannot Launch Debugger".I have checked this with my peers, and they does't face this issue :(

Also I don't have any issues while running the test.

It's an XP machine and following is the version of resharper:

JetBrains ReSharper 5.1 C# Edition
Build 5.1.1753.4 on 2010-10-15T15:51:30

Licensed to: XXXXXXX
Plugins: none.
Visual Studio 9.0.21022.8.

Copyright © 2003–2011 JetBrains s.r.o.. All rights reserved.

Thanks, -M

Answer 1

I occasionally encounter a test that can't be launched with the Resharper debug icon (due to mock objects or 32 vs 64 bit dlls). A solution that works for me is to add an explicit call to launch the debugger in the test

Debugger.Launch();

Then just run the test as normal. When code execution hits that line you get a security popup (pick yes)

then a visual studio choice popup (pick your currently running visual studio).

You'll be dropped into your code in debug mode at the location where you added the Debugger.Launch() line.

Answer 2

Possibly of use to someone stumbling here, specifically, I encountered the error:

---------------------------
ReSharper – Unit Testing
---------------------------
Cannot launch debugger.

Error code: 89710016

Error message: 0

when using R# 8.2 on VS 2013 Pro when attempting to debug NUnit tests.

After finding this link, the issue resolved by changing the NUnit class library project to x86 (Properties -> Build -> Platform Target : x86)

Answer 3

Instead of changing the build properties of the Project to be x86 (which can impact other team members if working on a team), you can tell Resharper to run the unit tests in a 32 bit process.

Resharper -> Options -> Tools -> Unit Testing ->General -> Default Platform Architecture

Set this to "Force tests to run in 32-bit process"