Cosmos Library location reset at computer boot

[glennco]

Hello,
Any idea why the library changes from d:\Chaos Cosmos (desired, and used for the last few years) to C:\Users\gardi\Documents\Chaos Cosmos, every time I start my computer?
I have to check Cosmos settings and reset the first time I open Rhino for the day. Once it’s re-set it stays on D: until I power down.
Thanks,
Glenn

V-Ray for Rhinoceros 8 • 7.20.02 • (598801 c7f85f1d) • Dec 1 2025
V-Ray Core • 7.20.05 • (ca2f0e7d)
V-Ray NeUI • 7.2.2 • (3811768 6116d056) • Nov 28 2025

Rhino 8 SR28 2026-2-10 (Rhino 8, 8.28.26041.11001, Git hash:master @ b7874a05a6982d0419fcc4f6009b510b48a09cb3)
License type: Commercial, build 2026-02-10
License details: Cloud Zoo

Windows 11 (10.0.26200 SR0.0) or greater (Physical RAM: 63GB)
.NET 8.0.24

Computer platform: DESKTOP

Standard graphics configuration.
Primary display and OpenGL: NVIDIA GeForce RTX 4070 Ti (NVidia) Memory: 12GB, Driver date: 12-30-2025 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 591.74
> Accelerated graphics device with 4 adapter port(s)
- Windows Main Display attached to adapter port #0

Secondary graphics devices.
AMD Radeon™ Graphics (AMD) Memory: 1GB, Driver date: 6-10-2025 (M-D-Y).
> Accelerated graphics device with 5 adapter port(s)
- There are no monitors attached to this device!

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
GPU Tessellation is: On
Redraw scene when viewports are exposed: On
Graphics level being used: OpenGL 4.6 (primary GPU’s maximum)

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: High

Vendor Name: NVIDIA Corporation
Render version: 4.6
Shading Language: 4.60 NVIDIA
Driver Date: 12-30-2025
Driver Version: 32.0.15.9174
Maximum Texture size: 32768 x 32768
Z-Buffer depth: 24 bits
Maximum Viewport size: 32768 x 32768
Total Video Memory: 12282 MB

Rhino plugins that do not ship with Rhino
C:\Program Files\Chaos\V-Ray\V-Ray for Rhinoceros\V8\VRayForRhino.rhp “V-Ray for Rhino”

Rhino plugins that ship with Rhino
C:\Program Files\Rhino 8\Plug-ins\Commands.rhp “Commands” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 8\Plug-ins\RhinoLabsTools.rhp “Rhino Labs Tools”
C:\Program Files\Rhino 8\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\RhinoRender.rhp “Legacy Rhino Render”
C:\Program Files\Rhino 8\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino 8\Plug-ins\MeshCommands.rhp “MeshCommands” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\IronPython\RhinoDLR_Python.rhp “IronPython” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\RhinoCycles.rhp “RhinoCycles” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 8\Plug-ins\BlockEdit.rhp “BlockEdit” 8.28.26041.11001
C:\Program Files\Rhino 8\Plug-ins\Displacement.rhp “Displacement”
C:\Program Files\Rhino 8\Plug-ins\Calc.rhp “Calc”
C:\Program Files\Rhino 8\Plug-ins\SectionTools.rhp "SectionTools"​

[hristo_chakarov]

Hello,

Are you the only one using this computer, or there are multiple users?

[glennco]

@hristo_chakarov
I"m self-employed and the only user of this computer.
Could this be related to the other cosmos problem we discussed ( Chaos Cosmos Browser Failed to load) or somehow to the Cosmos reinstall I performed trying to correct that problem or to a recent reinstall of Rhino trying to correct a UI problem when using saved views?
Glenn

[glennco]

@hristo_chakarov
I just started Rhino, and Cosmos was reset to C:\Users\gardi\Documents\Chaos Cosmos.
I worked late last night and it was set to d:\Chaos Cosmos.
I use a default starting template in Rhino that also has Vray settings that I prefer, (high quality, progressive, system memory for texture, etc).
After resetting Cosmos path to D: I resaved the template.
Note, I have done that step the last few mornings after I discovered this switching issue. and it doesn’t stick.
could this be related to the default start template or does Cosmos store it’s settings somewhere else that has been corrupted?
Glenn

[hristo_chakarov]

Hm that’s a really strange case. We’d need the log file, but for that purpose, please create a new issue in our support system.

[glennco]

@hristo_chakarov
I think it is related to the other problem we discussed in December.
https://forums.chaos.com/forum/chaos-cosmos/chaos-cosmos-in-v-ray-for-rhino/1233984-chaos-cosmos-browser-error
as the dates match to when Cosmos started writing to C: vs D:
what logs do you need & where are they located.
I’ll send them to support.
Glenn

[glennco]

@hristo_chakarov
thanks,
what logs & where are they located that I need to send to support?
Glenn

[hristo_chakarov]

@glennco , can you please try the following and see if it makes any difference:

1. go to C:\ProgramData\Microsoft\Windows\Start Menu\Programs\StartUp
2. Open Properties of CCBService shortcut
3. In the Target, please change the “30s” to “2m”
   
   
4. Apply and OK
5. Restart your computer 4-5 times and see if Cosmos selects the correct working (download) directory

Note: this change makes Cosmos auto-start 2 minutes after Windows start/user login.

Warning: If Cosmos Browser gets updated, this setting will be reset.

Let us know the result.

[glennco]

@hristo_chakarov

Thank you for your effort & clear instructions.
That worked!!!

This morning I:
started computer
unlocked D: BitLocker
set to 2m
restart
unlocked D: BitLocker (right away)
opened Rhino
opened Cosmos>settings> download path is D: (desired location)

thanks for mentioning to re-set that after cosmos library update.

Can you code that service at startup to see if D: is locked or unavailable, then pause for a couple minutes & check again?

I think I am going to change the 2m to 3m or 4m to give myself more time.
or can I manually stop/start that service if I get distracted and forget to unlock D: quickly after boot?

Glenn

[hristo_chakarov]

Oh yes. Actually that’s the correct approach in your scenario (where a manual action to unlock D drive is required after login).

Simply:

1. Open Start menu;
2. Type “Cosmos”
3. Choose “Stop”, then repeat 1 and 2 and choose “Start” in order to restart

Or if you prefer, you can disable (turn OFF) Cosmos autostart from the Autostart apps (again from Start menu) and start it manually.

If that works for you, that would be best.