June 21, 2018—KB4284833 (OS Build 14393.2339)

Improvements and fixes

This update includes quality improvements. No new operating system features are being introduced in this update. Key changes include:

• Addresses a performance regression in App-V that slows many actions in Windows 10.

• Addresses an issue with the placement of text symbols in right-to-left languages.

• Addresses a system crash (Stop 3B) in win32kfull.sys when cancelling journal hook operations or disconnecting a remote session.

• Addresses an unexpected logon termination issue with a third-party Remote Desktop Service (RDS) application.

• Addresses an issue where customers had to press Ctrl+Alt+Delete twice to exit assigned access mode when autologon was enabled.

• Addresses an issue that causes the full-screen Start menu to stop working when logging in.

• Addresses an issue that causes the system to log negative events for valid binaries that should be trusted. This issue occurs when running the Windows Defender Application Control (Device Guard) in audit mode.

• Addresses an issue that causes sporadic authentication issues when using Windows Authentication Manager.

• Addresses an issue that displays unnecessary “Credential Required” and “Do you want to allow the app to access your private key?” messages. This issue occurs when running a Universal Windows Platform (UWP) application.

• Addresses an issue that causes the LSASS service to become unresponsive, and the system needs to be restarted to recover.

• Addresses an issue where client applications running in a container image don't conform to the dynamic port range.

• Addresses a memory leak in RtlDosPathNameToRelativeNtPathName. The leak occurs when you turn on LongPathsEnabled in the registry and you call CreateFile or any other name-based Win32 API using a path that is longer than 260 characters.

• Addresses an issue where chkdsk doesn't update the file size and the valid data length when it needs to shrink the Master File Table (MFT) attribute list. This prevents the mounting of the next volume because NTFS considers the volume damaged, and rerunning chkdsk won't fix this.

• Addresses an issue that causes poor CPU performance when Virtual Switch Ports leaked during a machine’s live migration from one host to another.

• Addresses an issue where certain VMs with dynamic and startup RAM set at 32 GB restart with a blue screen. The error that appears is “PFN_List_Corrupt 0x4e”.

• Addresses a Windows 2016 Hyper-V environment issue in which creating a VM on a Server Message Block (SMB) 3.0 share may cause automatic registration to Hyper-V Manager to fail. This issue occurs when performing a backup for restoration to an alternate location. The error is "The Hyper-V Virtual Machine Management service encountered an unexpected error: The file or directory is corrupted and unreadable. (0x80070570)."

• Addresses a Windows Server 2016 Hyper-V host and guest migration issue in which a 2016 SQL file stream restoration fails with an “Event ID 11” error. The issue also causes the SQL process to stop working.

• Addresses an issue in which restarting the Hyper-V host with Hyper-V Replica (HVR) enabled could cause replication to stop. It may also require a manual restart to "resume the replication" from a suspended state. The replication state should be normal after the Hyper-V host/VMMS is restarted.

• Addresses an issue that sometimes prevents users from starting Microsoft Outlook after logging on to a Remote Desktop session.

• Addresses an issue in dfsutil.exe that occurs when exporting a DFS namespace as an XML file. The issue occurs when the namespace contains a link with a target that points to a shared folder that has an "&" character in its name. As a result, the generated XML does not correctly escape the "&" character, and dfsutil.exe cannot export the namespace.

• Addresses an issue that causes a connection failure when a Remote Desktop connection doesn’t read the bypass list for a proxy that has multiple entries.

• Addresses an issue that prevents VMs in an RD Pooled Desktop Collection from being recreated if the VMs are Gen2.

• Addresses an issue in a Remote Desktop VDI deployment that prevents a mounted UPD from disconnecting, which results in the creation of temp files.

• Addresses an issue in which the user interface for Windows Server 2016 Server Manager > File and Storage services displays the NVDIMM-N (memory) bus type as UNKNOWN.

• Addresses an issue in which the system event log receives many error events for IPRIP 29031 when the system receives the ERROR_OBJECT_ALREADY_EXISTS error.

• Addresses an issue that occurs when running Test-SRTopology between two clusters and their CSV paths. You may receive the error "Could not find file."

If you installed earlier updates, only the new fixes in this package will be downloaded and installed on your device.

For more information about the resolved security vulnerabilities, see the Security Update Guide.

Known issues in this update

How to get this update

To download and install this update, go to Settings > Update & Security > Windows Update and select Check for updates.

To get the standalone package for this update, go to the Microsoft Update Catalog website.

Prerequisite: The servicing stack update (SSU) (KB4132216) must be installed before installing the latest cumulative update (LCU) (KB4284833). The LCU will not be reported as applicable until the SSU is installed.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4284833.