I was having problems connecting a new computer to my network - it worked perfectly from the new computer, but none of the others could connect to it!
Searching Google I got the idea that maybe it was due to the fact that I had ascribed a different username to Admin on the new computer!
So I thought I'd revert to the old Admin username, which Windows 7 happily did for me, but kept the old username as a kind of alias. in all folder related issues.
The upshot of it all was that it did not solve my network connection problems!
So then I happened across your tutorial and followed it to the letter, but still no network joy.
Consequently I did a registry search for my old Admin username, and found hundreds of entries that had not been changed!!
I laboriously renamed all the relevant entries (I couldn't just do a search and replace on a copy of the registry because I had given my new computer the same name, although thinking about it now, perhaps I should have renamed the Computer first!).
Anyway, doing all this renaming in regedit solved all the problems attendant with your method (eg Task Manager Username, bad path messages, etc.) but it did not fix my Network Issue!
It was then that I got the idea to check Administrative Events for errors and happened across EventID 30013 (The DHCP Allocator has disabled itself on IP address 192.168.2.8, since the IP address is outside the 192.168.137.0/255.255.255.0 scope from which addresses are being allocated to DHCP clients. Etc., etc.)
It recommends to change either the scope or the IP address, but no-one seems to know how to do change the scope, which was my only option!
I searched Google for ages, and, although EventID 30013 was a very common complaint, nobody had the solution!
Then I had a stroke of lucky ingenuity!
My new computer has a wireless connection, (nothing new in that because I have another one which functions perfectly on a WIRELESS CONNECTION) but it worried me that the Local Area Connection was disabled - network cable unplugged (after all it was a Local Area Connection Problem).
So I right-clicked on my Wireless Network Connection, and soon realised that if I selected the 2 Connections with a box (hold down left mouse-button and select both Network Connections) then I could bridge them!
At first it complained of an error, then thought better of it, and realised the Bridge.
Eureka!
No more Network Connection Problems, no more EventID 30013!
If anyone else wants to Bridge their Network Connections I should point out that the Network Connection Control Panel is not directly accessible, even from the expanded Control Panel, but if you go to the Control Panel> Network and Sharing Center and select the 3rd item down on the left Sidebar (Change Adapter Settings) you will arrive at the Network Connections Control Panel.
Otherwise go to Start and type ncpa.cpl in the search box and it will appear at the top!
:)