OK guys so I noticed that there are lots of people who seem to be having this same problem logging into the new Windows Live Messenger, This is the method to fix ERROR : 8100030d
If you do your research on the Internet, you will see that Microsoft gives you a method to fix the following error, and kudos to them for their effort. Unfortunately this method is wrong and does not help.
This way is quick effective and I have never ever heard of any side problems, or anything of the sort.
This is the fix for Windows Vista, I am not aware or sure if this works with windows XP; but you could try. Alternately some things would probably be different.
1. Click on START
2. In the bottom search box type RUN and press Enter
3. In the window that appears type in the following regedit and hit Enter
4. In the window that comes up navigate to HKEY_CURRENT_USER on the left pane of the window.
5. Navigate down to Software and open it
6.Once again navigate down to Microsoft
7. Then Go down and open Windows live contacts and click on Database
8. Once You Get To This Point Your Almost Done, When you clicked Database a list should have come up in the right side of the window.This is basically the informartion consisted of the email adresses that have logged onto messenger on this computer.
All Your Going To Have To Do Is Delete 2 Files:
C:\Users\ Your Windows logon name \Contacts\ Your Messenger e-mail address
C:\Users\Your Windows logon name \Contacts\ Your Messenger e-mail address \ shadow
*[[Basically The 2 Writen With Your e-mail Adress]]*
Alrighty then, you guys should be done the process now! Once all of the steps are complete attempt to log in again and it should work. . If not please let me know.