SketchUp needs to decouple the Windows Thumbnail Provider registration ({e357fccd-a995-4576-b01f-234630154e96}) from .skb files.
Because .skb and .skp share a unified Shell Extension handler, Windows 11 forces active 3D model previews onto backup files.
This creates a severe user-experience risk on a free-form Desktop, as users cannot visually distinguish between a master project and a stale backup during fast drag-and-drop operations.
After that, check and make sure the file association is removed by right clicking on an SKB file and going to properties. It should hopefully go back to Opens with: Pick an app. But, if it still persists, run through these commands:
Could also make a simple bat file to run this. Maybe this doesn’t qualify as “simple,” but it gets the job done.
Personally, my Sketchup does not associate SKB to a file upon install; it never has. The only time it does is if I accidentally associate it via Right Click → Open With → Sketchup and accidentally set this as the default.
This has NOT fixed my setup.
HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.skb does not exist at all ?? What icon does a SKB display on your system ?
this is recent right ? It used to be that skb were blank pages, and I noticed yesterday that the skb on my desktop were showing a preview. this is definitively not old, I’m pretty sure last week or two it was still blank. darn updates.
yeah, it’s annoying enough that on macs, it’s not .skb but ~.skp (so many people don’t pay attention and reopen their backups…) now if even the skb system is flawed, where are we going ?
(also, sidetracking, can we please have the same .skb system on both mac and pc once and for all ? it’s 2026 ffs)
Ahh, I see the problem. Do you have your icons at medium or larger, per chance? I keep everything typically in a list/detail view in Explorer, which keeps to small icons, so I only see a blank document (Meanwhile I see a sketchup icon on actual SKP files).
But, as I increase the size of my icons in file explorer, I see your point. Anything around medium or higher begins to show the project file in the thumbnail view.
That’s no longer the file association handler, that’s the thumbnail handler. So I was way off the mark there; removing file association isn’t gonna do jack. My bad.
taskkill /f /im explorer.exe && del /f /q "%localappdata%\IconCache.db" && del /f /q "%localappdata%\Microsoft\Windows\Explorer\thumbcache_*.db" && start explorer.exe
Use with care [backup your registry beforehand if you are at all unsure]
It would be much better to be a different icon for SKP & SKB always !
@Arcwalde - Explorer windows with details list are no problem as you can sort to avoid SKB filetype etc, BUT on the Desktop with medium or larher icons it’s plain confusing !
Yeah I try to keep my desktop clutter-free of such things, but if you live off of your desktop then yeah, I can see how that’s a problem.
Here’s another easy fix, though it also stops showing thumbnail previews for everything
Open File Explorer
Go to the three-dot action menu
Go to Options
Go to View
Check “Always show icons, never thumbnails”
Even at larger sizes all you’ll get is the blank thumbnail icon. And all your SKP files will show with the Sketchup icon. This will also apply to icons on the desktop.
during training sessions, I’ll either save / export stuff in my download folder or straight to the desktop so I can quickly access them (I’m talking stuff that will get trashed when the session is over)
and that when I got the surprise.
in list you’re right, it’s still ok.
true. we could have a different icon for skb with a different colour maybe ?
It’s useful to see the SKP image on your Desktop icons.
It is not useful to see the SKB image - that should be the default logon icon.
In folder-windows I use detailed view so I can sort lists by filetype. BUT really the backup file [SKB] should not shown its contents - because on the Desktop with sensibly sized file icons you want to see the SKP image, and you do not want to see inside the SKB as that makes file identification awkward…
Almost all similar apps use a different file icon for their backup files [see AutoCAD for example].
It’s not rocket science to do this - but SketchUp conceals its ico files inside itself, so you can’t easily [i.e. at all] access them.
My registry hack above removes the SKB’s icon completely and defaults to a better, but poor ‘blank’ file icon. If we could access the basic SketchUp .ico file it’s be much easier, until ‘they’ fix this mess…
I now have a working solution - which Is pretty easy to do…
I extracted the SketchUp .ico file from its exe using a free PC utility called “IconsExtract” - by https://www.nirsoft.net/utils/iconsext.html
I edited it in Gimp to have a washed-out paler-blue color and a red-dot bottom-right to differentiate it from other icons. You can do the same, or edit the file I’ve attached here. Unzip the contents… SketchUp_IDR_MAINFRAME-SKB.zip (19.7 KB)
Next add the .ico path to the SKB set up in the Registry - Make a Notepad++ file on your Desktop named “SKB_icon.reg”
Copy/paste this text into it and save it.
Windows Registry Editor Version 5.00
; 1. Register the extension globally
[HKEY_CLASSES_ROOT.skb]
@="SketchUp.BackupFile"
; 2. Define the global file class icon mapping
[HKEY_CLASSES_ROOT\SketchUp.BackupFile]
@="SketchUp Backup Document"
[HKEY_CLASSES_ROOT\SketchUp.BackupFile\DefaultIcon]
@="C:\Program Files\SketchUp\SketchUp 2026\SketchUp\SketchUp_IDR_MAINFRAME-SKB.ico"
; 3. Mirror the class mapping to User Classes to enforce priority
[HKEY_CURRENT_USER\Software\Classes.skb]
@="SketchUp.BackupFile"
[HKEY_CURRENT_USER\Software\Classes\SketchUp.BackupFile]
@="SketchUp Backup Document"
[HKEY_CURRENT_USER\Software\Classes\SketchUp.BackupFile\DefaultIcon]
@="C:\Program Files\SketchUp\SketchUp 2026\SketchUp\SketchUp_IDR_MAINFRAME-SKB.ico"
; 4. Kill the protected user application overrides that block the icon
[-HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts.skb\UserChoice]
[-HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts.skb\OpenWithProgids]
Run that reg file by double-clicking it - accept the danger warning [there’s no warranty given, but it is pretty safe].
The Registry is now set up right, but nothing will have changed visually on your Desktop regarding SKB files.
So now you need to fix Windows Explorer and the Thumbnail cache.
Open a cmd window as admin [through the Windows / Start menu].
Paste the following text and enter.
Explorer will die, the thumbnail cache will be deleted and remade, and then Explorer will restart…
Now the new SKB icon should appear on all such files, even when SKP files show their contents.
