title: Cannot export solution from one organization to another
body: <p>We work with 2 organizations. One test and one production, the test is where we do all the work on an unmanaged solution. Than we export it managed and import on the production. This has worked without a problem so far. But when I tried it now I get the following error:</p>
  
  <p>A managed solution cannot overwrite a {0} component on the target system that has an unmanaged base instance.  The most likely scenario for this error is that an unmanaged solution has installed a new unmanaged {0} component on the target system, and now a managed solution from the same publisher is trying to install that same {0} component as managed.  This will cause an invalid layering of solutions on the target system and is not allowed.</p>
  
  <p>I assume this means something has changed on production and now can't be overwritten by the solution from the test environment. So I figured, no biggy, I'll just delete this from the test and try again. However the problem is it says that the issue is in Mappings, an Attribute map between quotedetail and salesorderdetail. These two have no relationship... So I went looking in the customization.xml and found the mapping.</p>
  
  <p>Here I found this:</p>
  
  <pre><code>&lt;EntityMap&gt;
    &lt;EntitySource&gt;quotedetail&lt;/EntitySource&gt;
    &lt;EntityTarget&gt;salesorderdetail&lt;/EntityTarget&gt;
    &lt;AttributeMaps&gt;
      &lt;AttributeMap&gt;
        &lt;AttributeSource&gt;ave_finishingid&lt;/AttributeSource&gt;
        &lt;AttributeTarget&gt;ave_finishingid&lt;/AttributeTarget&gt;
      &lt;/AttributeMap&gt;
    &lt;/AttributeMaps&gt;
  &lt;/EntityMap&gt;
  </code></pre>
  
  <p>finishing is a custom entity, which does contain a 1:N relation to both entities. So I tried to delete these relationships but I simply can't. It keeps giving me the error:</p>
  
  <p>Cannot Delete Component because one or more components require it. But there are no dependencies left on the relationships. I've deleted everything from forms, views, charts, even navigations... Still nothing when I select the relationship and click on show dependencies, it says there are none... I'm at a loss here on what to do.. I need to export the solution to production asap but am not allowed to edit the customization.xml, cause I figured I'ld just delete the entitymap there and it would work, which is probably true but also unsupported... Anyone have any ideas on what else I can do?? </p>