As said, I have solved the issue with random R0 and Error 30002. It was some settings on the actual network interface card for the computer I have running FFXIV.
These are the settings, and what they are set to for stopping Error 30002.
	
		
			
			
				Flow Control = Disabled
Interrupt Moderation = Disabled
Priority & VLAN = Disabled
			
		
 
	 
  To get to these settings, they are usually located in the Advanced tab of your Networking Controller in Device Manager.
1. Right Click 
My Computer or just 
Computer
2. Select 
Manage
3. Click on 
Device Manager
4. Expand the 
Network adapters list
5. Double Click on the network adapter listed (if you have more than one and not sure which one, just do this to all of them 
EXCEPT for wireless network cards)
6. Click on the 
Advanced tab
7. Select 
Flow Control and set the Value to 
Disabled
8. Select 
Interrupt Moderation and set the Value to 
Disabled
9. Select 
Priority & VLAN and set the Value to 
Disabled
10. Click 
OK
11. Reboot!