How to fix the SSMS LoaderPackage package did not load correctly

Question: I added a vendor based  SSMS plug in , and when starting SSMS  received the error message in a pop up window:          

    The 'Ssms2017LoaderPackage' package did not load correctly

I then clicked No - to the question - "Continue to show this message?". Restarted SSMS & the problem was fixed. i.e the plug in appeared.   The key point is I need to first navigate this error message & then restart SSMS

      These are the entries from the ActivityLog.xml , extracted from the path : <system drive>:\Users\<username>\AppData\Roaming\Microsoft\AppEnv\14.0\

<entry>

    <record>1</record>

    <time>2021/05/14 10:46:08.603</time>

    <type>Information</type>

    <source>VisualStudio</source>

    <description>Entering function xxxxxxxxxxxxxx</description>

    <guid>{xxxxxxxxxxxxxxxx}</guid>

  </entry>

  <entry>

    <record>2</record>

    <time>2021/05/14 10:46:08.603</time>

    <type>Warning</type>

    <source>VisualStudio</source>

    <description>Appid denied the loading of package</description>

    <guid>{xxxxxxxxxxxxxxxxxxxx}</guid>

  </entry>

</activity>

How can I troubleshoot &  fix?

Answer:  Based on the symptoms , I would say something is  happening such as: 

1) At the  first SSMS load, a registry key that the installer was supposed to add in HKCU is not present.

2) Check to see if this is happening with with multiple users (the user who installs is not the same one that logs in, or profile's registry entry changes clear down at login\logout . The aim being to identify if the issue relates to point 1. You may have a situation where every user needs to do this one off restart. 

3)Seems like you have a workaround - but contact the vendor of the plug in and review if the registry entries can be applied in a dynamic method - without requiring the restart.