I have this problem reproduced right now.
In this solution I have 4 C# executables, 1 library, and 4 setup and deployment projects.
All four c# executables have just one 1 form running a simple gui.
The solution layout:
C# exe1
C# exe2 <- this is selected as the startup project (select the project, right click and then click "set as startup project").
C# exe3
C# library
C# exe4
Setup1
Setup2
Setup3
Setup4
When I click any of the buttons in the VM Tool bar, I get the "Cannot find startup project" messages.
I also just discovered another clear, C# exe 4 happens to have been the FIRST product exe project I created in this solution. When I select it as the startup project, I don't get the error message. For other 3 exes, I get the "Cannot find startup project" message
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Buddy Lott
Firmware Design Engineer
19476 Industrial Dr.
New Paris, IN 46553
574.831.5250 x 8197