Disabling > Device Association Service = Can't Login

Hello Everyone
New to this great forum.
Was browsing for answers and arrived on this forum, found a topic but it is not related to my issue.
So I m very concerned about Windows 10 security and spying apps.
I have disabled many services in my Win 10 system for security concerns, but this service is a weird one, after I disable it I can't login after PC startup, there is no password and username fields just the background image. To solve this I must enable this service to Manual by booting in Safe Mode, after this I can login normally.
Did someone have such experience?
Why this non related to profile service causes such?
I have searched the entire Forum and Internet but I can't see similar issue posted!
On a side note I use build in Admin account.
P.s. I also disabled many security policies and many Windows 10 store apps by using W10Privacy software don't know if is related.
Thank you.