I posted this in the main SketchUp forum. But I thought it might also be appropriate here...
In newer versions of SketchUp... if you have your PC's Desktop on folders to display icons, then SKP files and SKB files look the same - with a model snapshot in them. In folders you can list by details to separate them out, but on the Desktop because they have similar names and icons it's then easy to drag-n-drop to email someone a file - using the SKB rather than the SKP which will be one-save newer.
I work out a simple Registry hack to fix this...
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. I can't get a ZIP to upload so try this zip Unzip the contents [.ico] SketchUp_IDR_MAINFRAME-SKB.zip.rbz …
Put the .ico file into the SketchUp folder as
"C:\Program Files\SketchUp\SketchUp 2026\SketchUp\SketchUp_IDR_MAINFRAME-SKB.ico"
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.
taskkill /f /im explorer.exe
del /f /s /q /a %localappdata%\Microsoft\Windows\Explorer\thumbcache_*.db
start explorer.exe
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.
