
If your Microsoft account is your internal account name might be just fredb. Doubleclick on the machine icon, doubleclick users and see what it says.

The easy way to see what name the file sharing software expects is to actually look at the Network (formerly Network Places) display. How do i find the name of the file sharing software? Go to the Share tab, and then in the Share with section, select Specific people. To share files with people in your workgroup or domain: Select the file or folder you want to share. To find out how to share files over a home network in Windows 10, see File sharing over a network in Windows 10. How do i share files over a network in windows 10? When it is time to change the credentials, you configure the change for the file share account and you do not need to update each individual subscription.

The file share account allows you to use a single set of credentials in multiple subscriptions that deliver reports to a file share. Now this is the important bit: The Microsoft account must have both "Share Permissions" and "Security Access" to any given shared folder.
