I'm a user who maintains low-level VBA tools for myself and some colleagues.
Some of the tools download or upload files from SharePoint online, treating the URLs as filepaths.
I'm not familiar with the mechanics of why this works, but I get the impression it has something to do with "WebDAV" (?) as I'm able to use filepath or url versions of the file locations.
Since upgrading to office 365, some of my colleagues have started to experience frequent "Access Denied" error messages when trying to interact with SharePoint online from Excel, Outlook and Access.
I don't have a clear idea of why this is happening, but my expectation is that SharePoint is validating the requests from my colleagues via some kind of onedrive or sharepoint online authentication ID stored somewhere as part of their federated identity management - everything is single sign on for MS at my company
In an attempt to deploy a more reliable method of accessing SharePoint, I stumbled upon the below, but I wasn't able to implement it because I don't have the user permissions to create an App in SharePoint.
After that, I reverted back to the idea that there already exists some type of authentication token or cookie that is stored on my colleagues computers or linked to their ID in some centrally accessible location.
I believe I may have a path forward in the solutions described in the below posts, but I'm struggling with where to begin with them - I can't even figure out where I would modify the code to add my company's specific SharePoint online domain name.
I'd love to figure this out myself, but recognize there is a considerable learning gap I need to overcome in order to get there. Can anyone recommend some good resources I could begin working through to get to a place where these solutions are more useful to me?