Default file location
Supported on: At least Windows Server 2008 R2 or Windows 7
Registry
HKCU
software\policies\microsoft\office\16.0\excel\options Options
defaultpath text Description
This policy setting allows you to specify the folder that Excel uses when opening or saving a file. This setting can be found under File tab | Options | Save | Save workbook Options. If you enable this policy setting, you may specify this folder. If you disable or do not configure this policy setting, the default folder will be used.