This PC, Computer or Documents Folder opens automatically at Windows Startup

Click Start > Run Regedit > Navigate To the following key:

HKEY_LOCAL_MACHINE\ SOFTWARE\ Microsoft\ Windows NT\ CurrentVersion\ Winlogon

In the right side panel, change value of Userinit to :

C:\WINDOWS\system32\userinit.exe

Now Navigate to the following key :

HKEY_CURRENT_USER\ Software\ Microsoft\ Windows\ CurrentVersion\ Explorer\ Advanced

In the right side panel, change the value of PersistBrowsers to 0.
Reboot your computer.