Sometimes when you are running QBO and debugging by attaching to process you will end up with a dozen or so ASP.NET development server processes. The way to stop this from occurring from the start is changing the properties in the Web Tier projects. The value Always Start When Debugging needs to be set to false as explained in this article.
So if you do a fresh pull from source or just forget to set them to false you have several instances of it running. You can go to the tray icons and remove them by right clicking or you do the following:
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