Hello again all

,
Just recently we added our first secondary domain controller to our network and since this we have been having lots of difficluties with active directory.
To begin with when i open AD it always looks for the secondary domain controller which is in our other states office, and this takes about 2 minutes to even open.
This however is not our biggest problem, the bigger issue is that when i create an object in AD on the main DC this object cannot be initialised for as long as up to 1 hour.
For example when i create a new user it sets it all up fine but when i go to log on using that account i get username and password errors for about an hour and then it just works.
Then when im finally in i go to set up there outlook account and get exchange errors when they are looking for the username.
Im not sure exactly what the problem is but it seems to be some sort of synching issues with the main and secondary DC that is causing these issues. The thing is this secnodary DC really does not have to talk to the main DC very often. All its really doing is authenticating one office in the morning and also being used to share one directory so it pretty much sits idle all day.
To be honest we dont even really need it, but we had an old server there sitting around gathering dust so decided to turn it into a DC.
So i guess what i am really asking is either does anyone know whats happening and how do we stop it? Or how do I tell it to only synch and talk to our main DC in the eveings so that it stops affecting me during the day.
I hope this makes sense because i am very new to multiple DCs and would like to iron out the issues as we have quite a few branches in different states that seem to be increasing every week and i can only see more of the same in the future.