Microsoft has pulled the latest Windows 10 Mobile build 10586.29 due to installation problems some Windows 10 Mobile users are experiencing. While a majority of Lumia 950 and Lumia 950 XL users were able to install the latest Windows 10 Mobile build without any problems, some Lumia 950 users are experiencing low storage error messages and others are experiencing problems installing Windows 10 Mobile apps.
In a post on Microsoft Answers, Microsoft let everyone know they're working on a fix for the Windows 10 Mobile build issue and are temporarily pulling the build off its public servers:
"We are aware of issues related to the recently published Windows 10 Mobile update, including: update not being offered, update appearing to get stuck at 0%, and pesky low storage notifications. The team is working on fixes and improvements to the upgrade experience in the short term and with future releases. In the meantime, we have unpublished the 10586.29 update for Windows 10 Mobile from our public update servers while we work through these reports. For those of you who still see the low storage notification: while bothersome you can safely ignore this message. For those of you who still have pending updates (OS or apps): make sure to plug your phone into a charger and leave untouched while it works through those items."
Those who have already installed Windows 10 build 10586.29 don't have to worry; you'll still be able to receive cumulative updates moving forward.