There are 3 scenarios I’ve included below related to material previews which appear black or do not render…
1. No 2011 Material Libraries Installed on Workstation
There are 3 items to check for material libraries not installed on the workstation. First you should receive the following dialog after Revit 2011 startup if this is the case:
If Do not show me this message again was checked previously, the Revit.ini will list the following line:
Next you should have no Render Appearance tab under Manage > Materials:
Lastly the Materials2011 folder should not be present under the C:\Program Files\Common Files\Autodesk Shared folder [or C:\Program Files x86 for a 64-Bit OS].
Before verifying the material libraries have never been installed on the workstation, ensure they do not appear in the Control Panel > Programs list. Once verified, the material libraries can be reinstalled at the following locations and order from the Without A Net post below:
2. Corrupt Material Library Installation
If the above folder is present, and the Autodesk Material Libraries appear in the program list, yet materials are not rendering at any quality the folders may be corrupt or incomplete. For this behavior, I would recommend uninstalling \ reinstalling the material libraries using the approach below:
Uninstall Material Libraries : Uninstalling the Autodesk Material Library 2011
Reinstall Material Libraries : Autodesk 2011 Material Libraries
If you do not have product media, the same folders are in the extracted download folder. By default the path would be as follows:
3. Rendering or previews appear black
Even at installation if the Autodesk Material Library 2011 Medium Image Library was not installed, you can still render at medium or above quality. Along with this, the render appearance previews should still display at medium or above.
If you receive previews that appear similar to the image below:
The following may have occurred:
-2011 beta installed on workstation, beta material libraries not uninstalled prior to install of final 2011 release \ materials.
-2011 material libraries uninstalled in incorrect order.
-2011 material libraries installed in incorrect order.
Regardless of the cause, you should be able to resolve the behavior above by simply uninstalling \ reinstalling the material libraries in the correct order outlined in the previous steps. The product does not need to be uninstalled \ reinstalled. And the medium image library does not have to be installed if it is not needed.
If you run into another scenario feel free to leave some comments below!