You can upload a the newer version of a file to the shared space by updating the file version. You can only update a file's version for files that you own, or in shared spaces where all members are permitted to modify files. When you update the file version you can leave a comment in the version history about your new version.

To update a file's version, follow these steps:

1. Access the shared space, and locate the file with which you want to work.
2. Click the file once to open the context menu, and then click View details. On the file details page, click Update version on the file panel at the top. The "Update Version" panel will appear.
3. Click Browse.... The "File upload" dialog box will appear. Locate and select the new version of the file from your computer. You will return to the "Update Version" panel.
4. You can leave a comment on the new version of the file (optional).
5. Click Save to upload your new version. If you do not want to update the file, click Cancel.