The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detail.

Problem:

Upon launching a .Net application, the error:

The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detail.

is received.

Solution:

The config file ended up having a ? character before the end of the element tag, like so:

    <startup>
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" ?/>
    </startup>

Removed that ? character and I was back up and running again.

Thankfully, in Visual Studio when building we get this error:

Error 1 Character '?', hexadecimal value 0x3f is illegal in an XML name. C:\Users\dprischak\Documents\Visual Studio 2012\Projects\IPCamFileSorterConsole\IPCamFileSorterConsole\App.config 4 75 IPCamFileSorterConsole