Why SketchUp Files Get Corrupted on OneDrive, USB, and Sync Folders

Many apparently corrupted SketchUp files are not caused by SketchUp alone. They break because the project was saved while OneDrive, Dropbox, a network share, or a USB device was also trying to move the same file.

Why Sync Folders and Removable Drives Cause Trouble

SKP files can be large and are often rewritten during save. If a sync tool or unstable removable device interferes during that process, you can end up with a partial or inconsistent file that still has the right name but no longer opens correctly.

SketchUp's saving documentation is unusually direct on this point: to avoid corruption or stability issues, it recommends local device storage or Trimble Connect instead of keeping the only live SKP copy in OneDrive, Google Drive, or a company network sync solution.

Safer Workflow for Active Projects

• Edit and save the working model on a local internal drive.
• Wait for the save to finish completely before copying anywhere.
• Sync only the finished file or a zipped archive of it.
• Keep at least one dated backup outside the active sync folder.

What to Try After a Bad Save

Stop editing the original, duplicate the file, and look for an older synced revision or an SKB backup. If the error message changed toUnexpected File Format, use this recovery guide as the next checkpoint.

How to Share Without Risking the Working File

Share a converted output instead of the live SKP whenever possible. For lightweight viewing, send GLB. For DCC work, send FBX or OBJ.