File Types Ignored or Blocked by Box Sync and Box Drive

Both Box Sync and Box Drive will not sync files that the program ignores or blocks. Ignored files include invisible in Windows Explorer or Finder, such as temporary or system files. Blocked files include file types that Box Sync or Box Drive does not recognize.


Box Sync still requires read permissions on these files in order to determine if the file should be blocked or ignored during the scanning process.


Box Sync and Box Drive ignore 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).
    • File names that start with a dot "." are considered hidden files.


  • Marking the Box Sync root folder as hidden deletes all synced content on
  • Hiding any file or folder in Sync also deletes that content.
  • Shortcuts created via Windows Explorer or Finder
  • Hard links (a file that has multiple directory entries associated with it will not be synced)
  • Symbolic links
  • Shortcuts created via Windows Explorer or Finder (.lnk)
  • File names that are exactly 8 uppercase hexadecimal digits (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E, or F) with no extension – for example: 1234AD38 or ABE32BD0.
  • File names containing special characters
  • Web based documents (such as .gdoc, .gsheet, and bookmarks) will not sync to the Box Sync / Box Drive folder, with the exception of Box Notes, which will be synced to the Box Sync / Box Drive folder and will open in your browser.
  • .qbi files


Box Sync and Box Drive block the following file types:

  • .pst
  • .qbw
  • .nd
  • .qbw.tlg
  • .tlg
  • .des
  • .qba
  • .qba.tlg
  • .qbr
  • .qby
  • .qdt

These file types can be uploaded and stored in Box via the Box web site, but Box Sync will not recognize them. They will not be synced even if they are in a synced folder.



Box Sync will sync folder names ending in a dot ("."), but users on Windows computers will not be able to access the folder. Users 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.


Microsoft Access database files (.accdb and .mdb):

Due to the saving behavior of Microsoft Access, it's likely that Box Sync and Box Drive will create duplicate copies of .accdb and .mdb files. Even one user working on a file can cause conflict copies due to how frequently Access makes changes to the database file.


We recommend pausing Box Sync prior to working in any .accdb or .mdb file. Then you can un-pause Box Sync when you are ready to upload the latest version.


Box Drive users can copy the file out of the Box folder and copy the file back into the Box folder after the changes are made to upload the changes to Box. 


Microsoft OneNote Notebooks: 

Microsoft does not recommend using synchronization programs like Box Sync or Box Drive with OneNote notebooks:


"In general, OneNote notebooks should always be synced and moved by the OneNote application, and not by file based synchronization systems such as a client application"

Please see for more information on OneNote syncing best practices.


Mac Package Files

Box Sync supports Mac package files. For more information, please see


Box Drive does not support Mac package files. You will see an error from Finder if you attempt to copy a package file into Box Drive. Package files uploaded by Box Sync will appear as problem items in Box Drive

Version history
Revision #:
36 of 36
Last update:
‎05-03-2019 12:59 PM
Updated by:


I have noticed in Box online, if you create a Bookmark in a folder for a web URL, this does not sync to user's Box Sync folders as a Windows shortcut. Likewise, if you create a Windows shortcut to a web page in your Box Sync folder, it does not create a corresponding Bookmark on box online. Is that correct?


Therefore, when someone using Box creates a link to a web resource from one place (Box Sync or Box Online), other people using Box (Online, or Sync) do not learn of its existence. This is quite too bad, and seems like it should have been make to work when building the Box Sync feature.

Hi @JG35,


Thanks for your suggestion and understand how the links not appearing on the local folder versus what you see on Box can be confusing. We've seen this feedback from others, so you can add your feedback here to this suggestion:

Thanks, @Howard !  I've gone ahead and done as you suggested.