You can disable the Protected View in Office through the Registry. The process is similar for all the Office apps, Word, Excel, PowePoint, etc.

1. Open your profile and go to the “Additional Registry Values.” 

2. Add a new entry.

Registry Location: HKEY_CURRENT_USER 
Registry Key: SOFTWARE\Microsoft\Office\16.0\Excel 
Value Name: DisableInternetFilesInPV 
Value Type: REG_DWORD 
Value Data: 1

Registry Location: HKEY_CURRENT_USER 
Registry Key: SOFTWARE\Microsoft\Office\16.0\Excel 
Value Name: DisableAttachmentsInPV 
Value Type: REG_DWORD 
Value Data: 1 
 

Registry Location: HKEY_CURRENT_USER 
Registry Key: SOFTWARE\Microsoft\Office\16.0\Excel 
Value Name: DisableUnsafeLocationsInPV 
Value Type: REG_DWORD 
Value Data: 1

In this case, it is valid for Excel version 16.0 if you are using the behind version, only change the number on the key, for example, (SOFTWARE\Microsoft\Office\15.0\Excel). You can use the same key concept for the other Office applications (Word, Excel, PowePoint, etc).​​​​