IDE can't Find OneWire.cpp

The problem is caused by using the Arduino IDE with files located under the OneDrive folder.

The easiest solution is to not use the Arduino IDE with any files in OneDrive.

In this case it looks like you have your sketchbook located under OneDrive. You can change the location of the sketchbook folder via the Arduino IDE's File > Preferences > Sketchbook Location. Change that setting to any convenient folder on your computer as long as it's not in the OneDrive. The Arduino IDE does not automatically copy the contents of the previous sketchbook folder to the new location so you will need to do this manually.

For more details on the problem, steps that are being taken to fix it, and possible workarounds that will allow you use the Arduino IDE with OneDrive, see: