TFPT not working with VS2015

Question

I am using Visual Studio 2015 and Team Foundation Power Tools 2015 and the explorer extension and the command line tool is not working. When i type tfpt in Devleoper Command Prompt for VS2015, i get the following error.

Unhandled Exception: System.IO.FileNotFoundException: Could not load file or 
assembly 'Microsoft.TeamFoundation.Common, Version=12.0.0.0,
Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its
dependencies. The system cannot find the file specified.   at
Microsoft.TeamFoundation.PowerTools.CommandLine.CommandLine.Main(String[] args)

I have run things in admin and that makes no difference. Here is what I get when i run the TF command.

C:\Program Files (x86)\Microsoft Visual Studio 14.0>tf
Microsoft (R) TF - Team Foundation Version Control Tool, Version 14.0.24712.0

TFS is working fine in VS. When I had VS2013 and TFS Power Tools 2013 everything was working fine. What else do I need to do to get this working?

edit: I have resolved the command line issue, but now the shell extension isnt working. I do not see the green check boxes in windows explorer, and when i right click a folder I do not get a TFS option. I am noticing multiple processes for it which is obviously does not seem good. Continues to create new processes until memory problems arise.

Additionally, Seeing these 2 events in the windows log.

Log Name:      Application
Source:        TFSShellExt
Date:          9/25/2016 7:25:40 PM
Event ID:      3
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      MyComp
Description:
TFS Shell Extension event:\n Failed to start COMProvider while updating workspaces.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="TFSShellExt" />
    <EventID Qualifiers="32770">3</EventID>
    <Level>2</Level>
    <Task>0</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2016-09-25T23:25:40.000000000Z" />
    <EventRecordID>156525</EventRecordID>
    <Channel>Application</Channel>
    <Computer>MyComp</Computer>
    <Security />
  </System>
  <EventData>
    <Data>Failed to start COMProvider while updating workspaces.</Data>
  </EventData>
</Event>

and

Log Name:      Application
Source:        TFSShellExt
Date:          9/25/2016 7:25:40 PM
Event ID:      3
Task Category: None
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      MyComp
Description:
TFS Shell Extension event:\n More than 5 failed calls to com provider. 
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="TFSShellExt" />
    <EventID Qualifiers="32770">3</EventID>
    <Level>3</Level>
    <Task>0</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2016-09-25T23:25:40.000000000Z" />
    <EventRecordID>156524</EventRecordID>
    <Channel>Application</Channel>
    <Computer>MyComp</Computer>
    <Security />
  </System>
  <EventData>
    <Data>More than 5 failed calls to com provider. </Data>
  </EventData>
</Event>

Answer 1

I just tested with my VS2015.3 and PowerTools on my machine, but couldn't reproduce your issue:

The error complains Could not load file or assembly 'Microsoft.TeamFoundation.Common, Version=12.0.0.0' , you may try to clean the cache in C:\\Users\\username\\AppData\\Local\\Microsoft\\Team Foundation\\x.0\\Cache to see whether it helps you.