Question:

When using the deployment script or the web installer, I am running into a deployment issue.  In my central administration, I am getting the following error message:
A feature with the ID [feature ID] has already been installed in this farm.  Use the force attribute to explicitly re-install the feature.  This error occurs when looking at the deployment status of a .WSP file in my solution store.  What do I do?

Answer:

If you run into this issue, use the following command in PowerShell to manually force deploy the .WSP file in question:
Install-SPSolution -Identity $SolutionName -AllWebApplications -GACDeployment -Force