If it is a new LUN the Solutions Enabler server that backs the Storage Viewer may not be updated with the latest LUN information. Did you go to Home > Solutions and Applications > EMC > Storage Viewer > VNX Systems and click Sync All Systems? Try that and refresh the storage viewer screen.
I have installed the latest VSI Plugin (5.2) on the vCenter server.  After creating a LUN on the VNX5300 with the plugin, the Storage Details show as incomplete, shown below.     The same is shown for a LUN that was created from within Unisphere as well.  Is this a bug in VSI?  I also had a question about the LUN expansion.  When expanding, does it create a metaLUN or not?  From what we could tell, it does not, which is what we prefer anyway.  Thanks for your help!
Bug in VSI?