How to prevent Visual Studio from building the project every time?

Question

When I right-click on a project and select Build, it builds it every time despite the fact that I just built it and the project is not out of date.

I've followed the instructions in the winning answer to a similar question, but that didn't resolve my problem.

I've also gone and made sure that Options/Project and Solutions/Build and Run settings were all correct. I turned on Detailed build output but didn't see anything obvious. The output is here: Part 1 and Part 2. The project itself if here.

The only thing that's suspicious is the following:

1>Project file contains ToolsVersion="4.0". This toolset may be unknown or missing

There is no ToolsVersion=4.0 in the project file.

Answer 1

Answering my own question in case anyone runs into a similar problem. The problem was that some files in the project (binaries and other non c# files) were set to Content/Copy Always. I changed them to Content/Copy if Newer and that fixed the issue.