Microsoft has just pushed Windows 10 Mobile Build 10586.122 as the latest cumulative update to Windows Insiders on  Slow and Release Preview Rings. So, if you are stuck in Fast ring with an older device, you need to open Windows Insider app and select Slow or Release Preview rings. We have shown in our hands-on video how to do this. We have also covered installation experience & First impressions of the Build 10586.122 on a mid-ranger Lumia 640 XL in our hands-on demo video,. You can read official changelog and known issues of Build 10586.122 by clicking here.

Installation Experience:

The Installation experience is pretty smooth with the Build 10586.122 and depending upon the device, it took around 35 to 40 minutes for the build to get downloaded, installed, data migrated and the devices getting up and running. You will be usually notified for a restart when the download has completed in background. It may require up to 1.20 GB of free storage. So, check the storage before you upgrade and you can check our tutorial on how to prepare for upgrade to Windows 10 Mobile.


The Build 10586.122 runs like a champion on the Lumia 640 XL. It is very consistent and polished. It packs many fixes to bugs and issues faced by Insiders with the last Preview Build 10586.122. The build offers a smooth performance across the UI navigation and is solid as a daily driver. We haven’t noticed any freezes or crashes so far, even nor for third-party apps. Coming to multitasking Build 10586.122 feels even more impressive and you won’t see the dreaded resuming screen. Microsoft Edge too feels much sorted out and renders pages faster than before. It also scores a respectable 442 / 555 in HTML5 test that we conducted. We must mention that we haven’t done hard reset on our devices but we recommend if you are facing lots of issues. We will come back with more detailed review of this build on a low-end device once we have used it for few days.

You can read our guide to fix commonly known Windows 10 Mobile upgrade, installation and usability issues.