[reversing_drive]

I have two computers on a LAN,
Both have D: drive shared
Both have a user called NETWORK with Password A (General Computer User Privelages)
Security on D: drive on both computers is Authenticated users only, not Everyone (which is default)

Now here's the problem:
After fresh boot from both machines, when computer 1 tries to access Computer 2's D: Drive, there will be a popup asking for username and password (Network usernamen used)
However if computer 2 tries to access computer 1's D: drive no username or password is needed, it just accesses without any hiccups.

How can i fix so both computers need to login to access on anothers drives?

Cheers,