Which File Types Are Ignored or Blocked in Box Sync?



Get Training

Box Sync ignores the following file types and shortcuts:

  • Temporary files and folders (.tmp and files starting with the ~ character)
  • Backup copies of files (.bak)
  • System and hidden files (hidden folders are synced but hidden files are not synced: such as ._dstore, desktop.ini, thumbs.db); Note: File names that start with a dot "." are considered hidden files
  • Shortcuts created via the Internet Explorer or Finder (.lnk)
  • Hard links (a file that has multiple directory entries associated with it will not be synced)
  • File names that have 8 uppercase hexadecimal digits (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E, or F)
    For example: 1234AD38 or ABE32BD0
  • File names containing special characters
  • Web based documents (such as .gdoc, .gsheet, bookmarks, and .boxnote) will not sync to the Box Sync folder

Box Sync blocks the following file types:


While these file types cannot be synced, they can still be uploaded into Box.com using a browser and stored in unsynced folders.

Note: Box Sync will sync folder names ending in a dot "." but users on Windows computers will not be able to access the folder. They will see an error dialog "Location is not available". Please remove the dot "." from the end of the folder name, or Windows users will be required to access the folder only from the Box web site.

Ignored files are not processed by Box Sync. Blocked files will prompt Sync to show an error icon overlay, and Sync will report them as problem files.

Was this article helpful?
75 out of 125 found this helpful