Not sure

Please switch on vMicro>compiler>verbose and also "show build properties"

Then click Build>rebuild

Then post the output as a .txt or email to info[at]visualmicro.com

Thanks

That's very interesting thank you.

We have another thread in this forum where the same error appears and now your report gives me more useful information.

The errors are because Visual Micro has stopped attempting to compile the project and you are seeing a standard Visual Studio C++ error with failed compile. 

The reason is not yet clear so I have some questions. 

1) Does the Visual Micro build button work correctly (not using Visual Studio Start Commands?

2) Can you please zip and email the project folder with all files and folders. (I will delete after I have looked at the file names and structure and will not look at the code)

Thanks very much

Okay that's useful thanks.

There are a few combinations that Visual Micro has to consider when determining if arduino can override Visual Studios default behavior. 

With standard configuration these are the rules.

The build/upload commands on Visual micro tool bars and menus use the project associated to the active code editor.

The Visual Studio "Start" and "Build" commands work the way visual studio normally works to determine the "startup" project.

The solution explorer can be confusing. There is a "tools>options>solution explorer" "Track active item" that can be switched off for less confusion. Then the >> arrow above the solution explorer is used to synchronize the Solution explorer with the code editor.

We have to consider what happens when a C# and and and Arduino project (2 different types of projects) are open in the same solution. Then more of this will make sense (i hope)