cannot install windows apps 0x800704d5

hello,
i formatted my pc cause its not running well (the os is windows 8.1 pro upgraded from windows 8) installed a clean copy of windows 8 pro from the installation disk (OEM disk with OEM License). i went to install an app (facebook) and an error occured 0x800704d5, it occurs on every app i try to download.
-i installed all windows updates.
-i'm able to install windows stock apps updates.
-i ran SFC /scannow command. nothing happened.
- i tried dsim commands. no issues found
but i realized that when i use my phone 4G hotspot to the pc theres no errors and the app installed properly.
i tried a dsl internet from my neighbors and the app installed properly.
Note: my internet connection is from a PPPoE ethernet cable connected through a router.
Is the problem from my internet connection? is it blocking microsoft services or something? or the problem is from windows (i installed windows from the oem disk like 5 time and the problem persists.