Why doesn't my .tfignore file ignore my packages folder

You can control this in NuGet.config.

Make sure the key "disableSourceControlIntegration" exists and is set to "true":

<solution>
    <add key="disableSourceControlIntegration" value="true" />
</solution>

References: http://docs.nuget.org/docs/Reference/Package-Restore http://docs.nuget.org/docs/Reference/NuGet-Config-Settings

If your packages are already in TFS, you should first "undo pending changes" on your local, delete them from TFS Source files and then, check in In Visual Studio. That will removed the packages from the server and will not ask to check them in again.