If you are using a SharePoint Online Document Center (you are using one to help manage documents, right?) – you may upload several documents at once. If you have turned on force check out – all of these documents will be uploaded but they will be left in a checked out state. That’s not good if someone else wants to edit them.
You can easily check them all back in with just a few clicks.
1) Go to your document center and click the checkboxes beside the documents you wish to check in.
2) Go to the Documents portion of the ribbon and look for ‘Check In’.
3) Click ‘Check In’.