This should work for all retail WP7 devices! You should start this guide from OS version 7008! (This should be automatically installed on a [registry] unbranded phone)
"Force NoDo" (March 2011) WP7 Update Guide:
Solution 1: Using your regular internet connection (Credits go to user Noticed) (Give him a Thanks here)
1. Start Zune.
2. Turn off data connection and Wi-Fi on the Phone.
3. Connect the Phone to the PC (USB).
4. Manually search for an update within Zune. ("Settings" > "Phone" > "Update")
Important step 5.:
About 3 seconds later, disconnect your PC from the internet. (Turn WLAN/Ethernet off)
6. The Update shows up!
7. Reconnect to the internet and install the update.
If it doesn't work try again starting from step 4 and vary the time you disonnect.
Solution 2: Using a VPN dialup connection
1. Download USAIP.pbk from here, then open it and connect to EUROIP PPTP Hungary
(This connection is automatically closed after 7 minutes! Check your firewall, if you have problems to connect!)
(If "Network Connections" doesn't open, apply the registry entry from here and reboot your PC)and connect your phone to the PC by USB.
2. Disable Wi-Fi (WLAN) in your phone, but be shure that airplane mode is off and that in "Settings" > "phone update" both checkboxes are checked.
3. Start Zune (if not already started) and keep it running all the time.
4. Switch to cellular settings on the phone.
5. Manually search for an update within Zune. ("Settings" > "Phone" > "Update")
Important step 6.:
After a few seconds (about 10-15 seconds for me, but this could vary from 5 seconds to almost one minute!) disable data connection on the already opened settings tab on your phone.
For the right timing utilize the timing trick mentioned below.
--> The update shows up!
(You can now terminate the connection and download the update using your "normal" internet connection)
If it doesn't work (cognizable by the fact that you get a time out error) retry steps 5 and 6 and vary the time until you manually disable the data connection! (step 6)Users report this tutorial works with WIFI! So if you aren't successful try to use your phone's WIFI connection instead of your cellular data connection (be sure to set the cellular data connection off this time).
(Thanks goes to vi3txlifv, mikmik111 and kapanak)
A trick to get the right timing (thanks Hardmen):
Get a stopwatch and stop the time until you get the Zune update time out. Subtract 0.5 to 1 seconds and that's the time you have to shut off the data connection.
Here is a nice video demonstrating the whole process. (watch after 3:00min) :
(Thanks goes to windowsphonehacker.com)
Please share your experience in the update procedure and participate in the poll!
Enjoy your phone!
Bonebreaker (a.k.a. ulub81)
Thanks also goes to dawnrazr and xsiriusx!
Even Paul Thurrott uses this method!