Microsoft Acknowledges Another Bug Brought by the Latest Windows 10 1903 Cumulative Update
The initial roll out may have been near flawless, but the Windows 10 May 2019 Update has now fallen into the same pandemonium of problems over problems. Regardless of how few users may be affected, it goes without saying that an update that is supposed to bring fixes should not be bringing more issues to users.
In the latest of these is a start up problem where some devices fail to start with users getting the 0xc0000001 error. Here is what Microsoft said about this latest problem:
Devices that start up using Preboot Execution Environment (PXE) images from Windows Deployment Services (WDS) or System Center Configuration Manager (SCCM) may fail to start with the error "Status: 0xc0000001, Info: A required device isn't connected or can't be accessed" after installing this update on a WDS server.
The problem has now been added to the list of known issues of the latest update KB4507453 that was delivered earlier this week. The Windows maker said that it is working on a resolution and will provide an update in an upcoming release. In the meantime, Microsoft has pointed to this workaround:
To mitigate this issue on an SCCM server:
- Verify Variable Window Extension is enabled. (This setting is not available on Windows Server 2008 SP2 or Windows Server 2008 R2 SP1)
- Set the values of TFTP block size to 4096 and TFTP window size to 1. For guidance on how to configure them, see Customize the RamDisk TFTP block and window sizes on PXE-enabled distribution points.
Note Try the default values for TFTP block size and TFTP window size first but depending on your environment and overall settings, you may need to adjust them for your setup. You can also try the Enable a PXE responder without Windows Deployment Service setting. For more information on this setting, see Install and configure distribution points in Configuration Manager.
To mitigate this issue on a WDS server without SCCM:
- In WDS TFTP settings, verify Variable Window Extension is enabled. (This setting is not available on Windows Server 2008 SP2 or Windows Server 2008 R2 SP1)
- In the Boot Configuration Data (BCD) of the imported image, set RamDiskTFTPBlockSize to 1456.
- In the BCD of the imported image, set RamDiskTFTPWindowSize to 4.
Note Try the default values for RamDiskTFTPBlockSize and RamDiskTFTPWindowSize first but depending on your environment and overall settings, you may need to adjust them for your setup.
More details on this workaround are available over here. The issue only affects Windows Server, but almost all the versions of Windows 10 appear to be affected, including 1903, 1809, and 1709.