Step-by-step guide

From the Box web application

1. To lock a file, click the drop-down menu next to the file and select Lock File.  A lock icon to the left of the file name indicates the file has been locked.  If you use Box Sync, you'll also see a lock icon over the file icon in your Box Sync folder.
   
   
   
   
2. When locking a file, you can select if you want others to be able to download the file while it's locked or choose an expiration time for the lock on the file to end so you don't have to unlock in manually.
   
   
   
   
3. Once you finish working on the file, you can click Unlock so other users can edit the file.  Don't forget to unlock your files if others will be working in it!

Locking files from your desktop using Box Sync

You can also lock and unlock files from your desktop using Box Sync.

1. To lock a file, right-click the file name in your Box Sync folder, navigate to Box Sync and click Lock.  
2. Once you finish working on the file, you can click Unlock so other users can edit the file.  Don't forget to unlock your files if others will be working in it!

Concurrently editing documents

If you need to edit a document simultaneously with another collaborate, you will need to use Word, Excel, or PowerPoint Online through Office365.  That is the only method for concurrent editing that Box supports.  See this video for more information: