PR4100 not visible on network after reboot

This always happens. I have a Windows 7 PC and its connected to a router along with the WD. I have various folders mapped as drives to the PC
Every time I restart the server I am unable to connect to it. Even by typing in its address*/

But if I do a hard reset on the box then it works, so basically every time I restart it, I have to do it twice.
This cannot be normal and I dont think ts very good for it.
I have no other external drives connected to the WD.
Any ideas anyone?

Hi, yes thats a good point but actually every time it starts and is ready it has been assigned the same IP address by the router anyway.