When you try to update a plugin assembly you sometimes get
an error saying the plugin assembly cannot be updated, the manifest of the plugin….etc…
This most probably could be that you are trying to update
the assembly which is in the database. However the same plugin could have been registered
in the GAC. Till you take the plugin out of the GAC you will not be able to
update the plugin.
Once you have taken
it out the plugin assembly would get updated without any issues.