I've found that whenever fiddler is running on my PC (most of the time), Office 365 apps are unable to authenticate, for example, word can't access SharePoint 365 documents and OneNote can't sync notebooks stored on my OneDrive or on the SharePoint 365. They just keep prompting for my password. As soon as I close Fiddler, they authenticate and everything works again. Once authenticated, I can run Fiddler again and they keep working for a bit.
Is there anything I can do to Fiddler's settings to get it to ignore Office 365 traffic?