title: CRM 2011 - Import Solution getting error Unable to load plug-in assembly
body: <p>Here's my story:  I've imported my CRM 4 solution to CRM 2011.  Most things look OK, plug-ins mostly work.  This import process was done through the CRM Deployment Manager.</p>
  
  <p>Step 2 I wanted to test building a Solution, adding all my customizations to it, export it, and import it to a second organization on the same server.</p>
  
  <p>Its gotten fairly close (its a HUGE improvement over CRM 4).  But its failing when it goes to load my plug-in assembly.  The CRM Trace and event log aren't providing me any more help than the solution import log file:</p>
  
  <blockquote>
    <p>Failure   0x80044191  Unable to load
    plug-in assembly.</p>
  </blockquote>
  
  <p>My assembly is deployed to disk so its available.  I tried unzipping the solution file, and adding my assembly in the solution hierarchy but that didn't help.</p>
  
  <p>Is it because they're CRM 4 plug-ins?  Must they be updated to be imported in CRM 5?</p>