Windows 2008 Server Blocking RDP IP Address Hacks
Find out the IP address of the Prick who is trying to hack your server.
Go to the Windows Event Log, and select Security. Look for the Audit Failure event and you will see the IP there.
Setup a custom rule in Firewall With Advanced Security to block this incoming IP from attempting a hack.
Start -> administrative tools > windows firewall with advanced security.
Select Inbound Rules / New Rule
Select Custom / Next
Select All Programs / Next
Leave Default / Next
Leave the Local IP set to ANY, but Change the Remote IP to ADD
Ensure that you have added the prick who is hacking you, then Next
Select Block the Connection / Next
Leave Default / Next
Give the rule a name / Finish