If you've been following along, you know the last Build release of Windows 10 for phones didn't go well for some participants in the Windows Insider program. Some Lumia owners found their handsets would brick during the update. Many more found the latest release to be almost unusable, even if installed successfully. And, this is a bit disconcerting for the Windows Phone faithful, considering Microsoft is now rumored to release Windows 10 sometime in late July.
To top it off, some (not all) Lumia 520/521 owners found that the Windows Phone Recovery Tool (WPRT), the actual application used to recover a failed Build installation or just to revert back to a supported Windows 10 version, would cause the smartphone to bomb and fail to recover. Specifically, owners were met with:
Displaying only a red Nokia logo
Displaying a black screen, with the device being non-responsive after attempting to boot
Microsoft believes it has figured out the issue, blaming available space and performance for a distinct subset of the 520/521 model. Essentially, WPRT was feeding the data blocks to the devices too quickly, causing the hardware to choke and bomb.
Microsoft has now released an updated version of WPRT, pushing it to version 1.2.4. Even with the new version, Microsoft has halted delivery of Windows 10 Technical Preview to the Lumia 520/521 models until the fix can be verified.
However, those that have WPRT installed, you might want to grab the latest version.
You can grab the latest version here: Windows Phone Recovery Tool (WPRT)
Due to the updated WPRT, Microsoft hopes to make the Technical Preview available again tomorrow...
@yogesharya2011 Yes we believe this is solved now with a change to WPRT and will offer again for 520s soon (likely late in the day tomorrow)— Gabriel Aul (@GabeAul) April 20, 2015