[WavingReds]

is there a way to downgrade my lumia 900 to 7.5 Tango? I'm not happy with 7.8 on it =/

[smsmith1975]

You'll have to reset to factory, and then run updates through Zune, but stop before you get to the 7.8 update.

[Microsoftjunkie]

is there a way to downgrade my lumia 900 to 7.5 Tango? I'm not happy with 7.8 on it =/

You should be able to just run Zune, check for an update, and you should be prompted with an option to revert back to previous.

[smsmith1975]

Yeah, I forgot about the restore point that was supposed to be made when you updated!

[WavingReds]

Ok, thanks guys! much appreciated, will try when I get home!!!

[RNicholas84]

I hate to hijack this thread but is there anyway to do this if you did a clean install on your computer and don't have the revert option? I re installed Windows on my laptop and had to re download Zune. So I non longer have the revert option.

[AniruddhDixit]

@RNicholas84, I have the exact same problem. I have lost my zune restore after my laptop crashed. Now i'm stuck with wp 7.8 which i completely hate due to the audio volume quality. Did you try doing a hard reset and then trying?

[WavingReds]

I believe your other alternative is to flash it backwards to 7.5

Nokia Lumia 900 - xda-developers may have the answer that you're looking for!

[ash29k]

Navifirm and Nokia care suite.. You can flash any version to your phone.. If not on Nokia good luck, I heard some "other" methods brick phones...

[scdkad]

You'll have to reset to factory, and then run updates through Zune, but stop before you get to the 7.8 update.

Are you sure a reset removes 7.8?

[ash29k]

Are you sure a reset removes 7.8?

no it will not. 7.8 is the os not an update. Restore or reinstall.. A reset will only kill off your apps and settings for 7.8 not reset to 7.5. Please research properly before taking advice off of someone who knows nothing.

[smsmith1975]

no it will not. 7.8 is the os not an update. Restore or reinstall.. A reset will only kill off your apps and settings for 7.8 not reset to 7.5.

You're saying a factory reset won't wipe it all the way back? I can see that being true if the phone originally came with 7.8, but if it came with something less, that was my understanding... all the way back to the day you got your phone. That was my experience when I had to factory reset my Lumia 900 that I had updated to 7.5. Factory reset completely wiped the phone out to the day it left the factory.

[joeaux]

Uh ash29k is right. If you upgrade to 7.8 a Factory Reset via the phone will put you back to a stock WP 7.8. If you can find the 7.5 ROM and flash it via Nokia Care Suite you will be back to 7.5. The XDA link above is a good start. Just read, read, read before you start flashing your phone. Know what you're doing or you'll end up with a pretty piece of polycarbonate and silicon. ;)
-joe-

[smsmith1975]

Ok, thanks for the clarification. My understanding prior to this was that the phone would be brought back to the state that it was in when it left the factory, as a fail safe in the event that anything catastrophic went wrong during an update or during usage. How that would be accomplished, I don't know... possibly a ROM chip that stored an image of the original install.

Anyway, thanks again.

[kki75]

The phone flash chip includes a boot block area that's usually not altered after leaving the factory. In case anything catastrophic went wrong with the OS during update or use, the fail safe is to boot Nokia DLOAD (I think it is hold volume down + power), which has just enough functionally to enable a service PC to load/flash an OS to the phone.

[Atul thengane]

plss can anybody help me out to downgrade 7.8 to 7.5 ,after upgrading to 7.8 i can't access my phone book ,cant read msgs, wifi,about and so..... plss help me out m in trouble just let me procedure and software to downgrade plsssssss