With shared storage of documents, overwriting other author’s work has historically been a concern. Two people would open the same document and made changes to the same content and whom over saves last wins and the other work is lost….. So as good technicians we have historically fought that scenario by requiring Checkout before editing. SharePoint would do this for us as soon as a user edited the file. A lock would be placed on the file until it is closed. Brilliant! I know those were good days.  

Question: With SharePoint online and the co-authoring options, is check-out and check-in a required default. I am sure there are still scenarios when you need to check out the file for exclusive access and control. Like you want to format the whole thing or apply document-wide content or settings. What is the process and best use of the document check-in and check-out using SharePoint Online? Is it different if you use Word Online, Word Desktop, or opening from a Synced?   

Set Up:

1. SharePoint Online 
2. Document library 
3. In classic mode Document library Configuration:  
   1. Library settings > Versions Settings > Required Check out in order to edit: Yes 
   2. Library settings > Versions Settings > Major versions, Limited to (500) 

Scenario 1: Edit with Word Online and Word Desktop starting from the browser 

Results: Make edits with Word Desktop not Word online, because you have to manually check-out and check-in as a separate step from selecting from editing the document.  

Word Online:  Must check out document separately before doing a second action of an edit.  

1. Rt. Click document > Advanced > Check Out 
   
   
2. Rt. Click > Open In Word Online
   
3. The document opens in edit mode
4. Make a change to the document
5. Click the link to in the blue ribbon o navigate back to the library and the edits will be auto-saved
6. If the version column is displayed in the current SharePoint view, the version number has increased
7. Check out is still on if editing in a browser (bad). Must be manually checked in.
   
8. Rt. Click the document > Advanced > Check in
9. The checked out icon disappears

Word Desktop: Must check out document separately before doing the second action of an edit.

1. Rt Click document > Advanced > Check Out
   
2. Rt. Click > Open In Word
   
3. Click the button (if prompted) Open Word (desktop), and check the box: Always open these types of links in the associated app.
   
4. Another dialog box opens. You will be prompted with this dialog each time you open an office document with a desktop version of the Office application.
5. Click the button: Yes
   
6. The document opens in MS Word and is in edit mode.
7. Make changes to document > Close
8. You are prompted to save and close
   
9. You are then prompted to check in the document
   
10. MS Word Desktop closes and you are returned to the SharePoint library
11. The check out icon is still displayed on the file. You must refresh the page in order to see the checkout icon disappear.

Word Desktop with files synced to the local machine: check out document separately before doing a second action of the edit.

1. Click the sync button on the library
   
2. You may need to get the lastest version of One Drive in order for the sync to work properly.
3. Open your Windows file explorer
4. You will have a new entry with the name of the {SiteName}-{LibraryName}. For example my site name is HR and the library is called EmployeeDocs would be HR EmployeeDocs
5. The lock icon to show you that there is a check out required
   

1. You cannot edit from a local file explorer without explicitly checking it out through the browser. They are ready only.
2. Once turned off then edits can happen
   
3. Double click a document
4. It opens in Word Desktop
5. Make changes to the file
6. Save and close the MS Word.
7. The status icon has changed to a Check to let you know the file has been synced and a local offline copy is available
   

Conclusion:

With SharePoint Online I do not think you should use Check-in and Check-out. It should be used as a requirement or default. With co-authoring being enabled for Word Online and Word Desktop. You will not get locked out, and with the version control, you can always go back and get an old version.