Rhino Thumbnail viewer not working - help!

I need help. Rhino 5 64 bit - Win7 64 pro
I had the RhinoThumbView_x64 working ok, then I must have done some registry cleanup, install (I installed an unistallder software that was too bossy, deleted it) and now no more thumbnails for my rhino files.
I have so far:

  • reinstalled Rhino5 on existing version
  • cleaned up all RhinoThumbView_x64 and reinstalled
  • checked and set the windows explorer “display thumbnails and not only icon” thing.
  • can’t go to previous registry restore point, too far in the past. Not sure if it is a registry problem, anyway, maybe just the 3dm files are not “seen right” by windows explorer
  • checked on the web any possible other viewer, installed and disinstalled (with registry cleanup) the setup_ThumbRhinoView extension, that supposedly works only on v.3-4 files
  • even XNview that was seeing the thumbnails is only showing the icon now.

I have used up all my resources to find a solution, I’m doomed. Is there anybody that can help me to see what is the problem and fix it.
Is there a thumbnail viewer out there that I am not aware of, a standalone, maybe?


there has been a discussion here:

follow the instructions in this discussion.

btw. try to avoid registry cleaners whenever you can. They do more harm than you can imagine and often a complete reinstall is required.


Hi Roberto,

Please try the following:

1.) Close all running copies of Windows Explorer

2.) Bring up an administrative command prompt

3.) Navigate to the following folder:

C:\Program Files\Rhinoceros 5 (64-bit)\System

4.) Run the following from the command prompt:

regsvr32 RhinoHandlers.dll

Does this help?

Hi Dale, thanks for helping.

  • I did everything exactly as you said
  • restarted computer (just in case)
    Nothing changed. Something must have gone wrong.

I received a couple notices, though, I’m attaching them.
Don’t know if the second one is related to this operation, I had 4 instances of Rhino open and was furiously working.