OneDrive is a useful cloud storage service, most of users like to save important files to OneDrive. The “OneDrive Cannot Connect to Windows” error message shown when the user trying to access files in the OneDrive folder if the user has previously enabled Files On-Demand in OneDrive settings.

To fix this error, you are suggested to try the following steps:
- Select the Start button and type: cmd
2. Right-click or long-press on Command Prompt and select Run as administrator.
3. Type or copy and paste the following command into the Command Prompt dialog:
reg add HKLM\System\CurrentControlSet\Services\Cldflt\instances /f /v DefaultInstance /t REG_SZ /d "CldFlt"
4. Restart your device after the command has completed.
5. To verify Files On-Demand is still enabled, right click or long press on the OneDrive icon in the notification area and select Settings.
6. In the Settings dialog, verify that Save space and download files as you use them is enabled, then select the OK button.
7. If you are using more than a single OneDrive account within the app or are using both OneDrive Personal and OneDrive for Business, you will need to repeat steps 5 and 6 for each account.
8. OneDrive app should now connect and run as expected.
If the error cannot be fixed. You can also try to reset your OneDrive. Here are the steps:
Step 1: Press Windows key + R to open the Run box.
Step 2: Type
%localappdata%\Microsoft\OneDrive\onedrive.exe /reset
and press Enter.

* “%localappdata%” refer to “%USERPROFILE%\AppData\Local”. For example c:\users\alex\AppData\Local
Step 3: Wait for the Microsoft OneDrive icon appearing in the notification area. If it does not appear, paste the command to the Run:
%localappdata%\Microsoft\OneDrive\onedrive.exe