Azure Caching - Failure after upgrading to SDK 2.1 and caching 2.1

Azure Caching - Failure after upgrading to SDK 2.1 and caching 2.1

It looks like there are a number of questions already open on this topic,
but I believe mine might be different. My setup:
1 Azure Cache Worker Role
1 Web Role
Up until about a week ago, they existed in harmony, until I tried to
upgrade to Azure caching 2.1. Once I did that, I was afflicted with the
"No such host is known" problem that seems to have affected many
developers out there. I found many questions and sites that directed me to
upgrade my Azure SDK installation to the new 2.1 version. I have done all
of these things:
Install newest Azure SDK 2.1
Uninstall Azure SDK 2.0
Uninstall and Reinstall Azure Caching 2.1
Triple check configuration of all my caching settings
Triple check that all references are pointing to the newest versions and
not the old ones
Upgrade my Azure Project to 2.1 by right-click, going to Properties, and
clicking Upgrade
and I am still getting the following (My Error):
Exception type: SocketException
Exception message: No such host is known
at System.Net.Dns.HostResolutionEndHelper(IAsyncResult asyncResult)
This is different than the more typical error that most other questions
and sites are showing, which is (More commonly reported error, not mine):
No such host is known
Exception message: No such host is known
at Microsoft.ApplicationServer.Caching.AsyncResultNoResult.EndInvoke()
I am about 30 hours into troubleshooting this, and could really use some
help. Maybe I am just missing some step about the upgrade of the SDK?
Somehow maybe sneakily it is still using an old version of a DLL? Is there
some foolproof way to check this besides looking at the path of every
reference in the project (which I have already done, and they all match
up)?