Unable to run multiple startup projects in Visual Studio 2015

Question

I'm using VS 2015 Enterprise Update 1, although this happened before update 1 as well.

At some point, I became unable to do CTRL+F5 (Start without Debugging) when my solution is configured with multiple startup projects. It doesn't matter what these projects are - in fact, I can have a single project selected in the multi-project dialog, and I get the same error.

The error is:

Unable to start without debugging. The startup project cannot be launched. Ensure that the correct project is set as the startup project. The startup project can be changed by selecting the 'Set as Startup Project' command from the right click menu in Solution Explorer.

Additionally make sure its debug settings are correctly configured in project properties.

I've confirmed that I can CTRL+F5 with individual projects, but never with multiple. This happens across multiple, totally independent solutions - and so appears to be some non-solution/project specific issue with Visual Studio.

I also tried running Visual Studio in Safe Mode and that made no difference.

Answer 1

I've just had the exact same thing and it turned out to be because I'd set every project to "Start without debugging". Seems that at least one project is required to to be set to just "Start" before it will run anything..