DHCP Archives

Winsage

September 23, 2025

7 ancient Windows commands that are still helpful for troubleshooting today

The Windows Command Prompt is a key tool for PC troubleshooting, especially for IT professionals. - Netstat -a -n -o: Initial release in 1983; used for diagnosing network errors by revealing active connections, ports, and their states. Parameters -a, -n, and -o provide additional insights. - Ping -n 100 IP or webaddress: Initial release in 1983; checks connectivity to a network location, measuring latency and hops. The -n parameter specifies the number of packets, and the -t option allows continuous testing. - ipconfig /release and ipconfig /renew: Initial release in 1998; essential for displaying network hardware status and resolving IP conflicts by refreshing network configurations. - DISM /Online /Cleanup-image /RestoreHealth: Initial release in 2009; maintains Windows installation images by checking and repairing the Windows Component Store. - Sfc /scannow: Initial release in 1998; verifies and repairs the integrity of the operating system, useful for resolving certain errors. - powercfg.exe /hibernate off: Initial release in 2004; disables hibernation to free up disk space by deleting the hiberfil.sys file. - OOBEbypassnro: Initial release in 2020; allows bypassing Microsoft account registration during Windows 11 installation, though its future is uncertain due to planned removal in an upcoming update.

Winsage

August 14, 2025

Microsoft fixes Windows Server bug causing cluster, VM issues

Microsoft has resolved an issue affecting the Cluster service and virtual machine restarts after the installation of July's Windows Server 2019 security updates. The problem, acknowledged in a private advisory, involved the Cluster service malfunctioning after the KB5062557 update, causing nodes to fail to rejoin clusters and virtual machines to experience multiple restarts. The August 2025 KB5063877 cumulative update has fixed this issue, requiring the prior installation of the KB5005112 servicing stack update. Additionally, Microsoft addressed a WSUS problem affecting the deployment of the August 2025 KB5063878 update on Windows 11 24H2 devices and resolved a DHCP service freeze issue caused by June 2025 security updates in the July 2024 cumulative updates.

Winsage

July 22, 2025

Microsoft: Windows Server KB5062557 causes cluster, VM issues

Microsoft has identified an issue with the Cluster service on Windows Server 2019 following the installation of the July security update KB5062557, released on July 8th. This issue causes the Cluster service to repeatedly stop and restart, leading to nodes failing to rejoin the cluster, entering quarantine states, and causing virtual machines to restart multiple times. Administrators using BitLocker on Cluster Shared Volumes may also face additional errors. Microsoft has advised affected organizations to contact their business support teams for assistance while a mitigation strategy is being developed. Additionally, Microsoft is working on a resolution to be included in a future Windows update.

Winsage

June 27, 2025

How to configure multiple DHCP scopes on one Windows server

Administrators use the Dynamic Host Configuration Protocol (DHCP) service to manage IP address configurations for clients efficiently. Deploying multiple DHCP scopes on a single server is more practical than having separate servers for each subnet. DHCP operates through a four-step lease process: discover, offer, request, and acknowledge. To install a DHCP server, the PowerShell cmdlet Install-WindowsFeature DHCP -IncludeManagementTools is used, and the server must be authorized in Active Directory. A single DHCP server can manage multiple scopes, each with specific configurations for different subnets, such as DevNet, ProdNet, SalesNet, and EngineersNet. Each scope can have unique IP address ranges and settings, and additional scopes can be created by adding network interface cards (NICs) to the server. Server options apply globally, while scope options are specific to individual scopes. Reserved IP addresses can also be configured within each scope.

Winsage

June 18, 2025

Microsoft broke DHCP for Windows Server last Patch Tuesday

Microsoft has acknowledged that the updates released on June 10 during Patch Tuesday may disrupt the Dynamic Host Configuration Protocol (DHCP) service on Windows Server versions 2025, 2022, 2019, and 2016. The DHCP Server service might intermittently stop responding after installing this security update, causing issues for network administrators as clients may be unable to renew their IP addresses. There is currently no viable workaround for affected users other than rolling back the patch, which is not ideal due to the critical security fixes included in the update. The impact of this issue varies among users, with some experiencing significant problems while others report no disruptions. Microsoft is working on a resolution and will provide further information soon. Additionally, Microsoft has faced challenges with its Surface Hub v1 devices, requiring an out-of-band update.

Winsage

June 16, 2025

Windows Server update may disrupt IP refreshes

Microsoft has acknowledged that the June security update has caused complications for users of Windows Server systems, specifically affecting the Dynamic Host Configuration Protocol (DHCP) service, which is failing and leading to improper functioning of IP refreshes. The issue impacts multiple versions of Windows Server, including 2016 (KB5061010), 2019 (KB5060531), 2022 (KB5060526), and 2025 (KB5060842). Users have reported that the DHCP service may stop responding after installing the update, with one administrator noting their 2016 server crashed shortly after the update was applied. Microsoft is working on a solution and advises affected users to uninstall the update to restore functionality. The company has a history of DHCP-related issues dating back over a decade and has faced other problems with Windows Server updates in the past year, including issues with keyboard and mouse inputs and authentication challenges.

Winsage

June 16, 2025

Microsoft: June Windows Server security updates cause DHCP issues

Microsoft has identified an issue with the June 2025 security updates that causes the Dynamic Host Configuration Protocol (DHCP) service to freeze on certain Windows Server systems. This affects the service's ability to apply renewals of unicast IP addresses, impacting network operations. Microsoft has acknowledged that the DHCP Server service may intermittently stop responding after the update and is working on a resolution. Additionally, other issues affecting Windows Server systems have been addressed, including application failures and authentication problems on domain controllers. Out-of-band updates were previously issued to fix bugs causing Hyper-V virtual machines to restart or freeze, and emergency updates were released for issues with Windows containers on certain Windows Server versions.

Winsage

June 11, 2025

Microsoft June 2025 Patch Tuesday fixes exploited zero-day, 66 flaws

On June 2025 Patch Tuesday, Microsoft released security updates for 66 vulnerabilities, including one actively exploited and one publicly disclosed zero-day vulnerability. The updates addressed ten "Critical" vulnerabilities, with eight being remote code execution vulnerabilities and two related to elevation of privileges. The breakdown of vulnerabilities includes 13 Elevation of Privilege, 3 Security Feature Bypass, 25 Remote Code Execution, 17 Information Disclosure, 6 Denial of Service, and 2 Spoofing vulnerabilities. The actively exploited zero-day vulnerability is CVE-2025-33053, a WebDAV Remote Code Execution vulnerability, while the publicly disclosed zero-day is CVE-2025-33073, a Windows SMB Client Elevation of Privilege vulnerability. Other companies also released updates in June 2025, including Adobe, Cisco, Fortinet, Google, HPE, Ivanti, Qualcomm, Roundcube, and SAP, addressing various vulnerabilities across their products.

Winsage

April 26, 2025

Windows 11 KB5055627 update released with 30 new changes, fixes

Microsoft has released the KB5055627 preview cumulative update for Windows 11 24H2, which introduces new features and bug fixes. This update is part of optional non-security preview updates and does not include security updates. Users can install it via Settings under Windows Update or download it directly from the Microsoft Update Catalog. The update elevates Windows 11 24H2 systems to build 26100.3915 and includes features such as Recall (preview), Click to Do (preview), improved Windows Search, Narrator enhancements, Phone Link, interactive Widgets, curated views in File Explorer, updated Settings for app recommendations, and Windows Studio Effects. It also addresses bugs related to blue screen errors, DHCP Client connectivity issues, Windows Hello functionality, and provides estimated offline times for updates. Notable issues include potential installation blocks for Citrix components and download issues for Roblox players on Windows Arm devices, with workarounds available.

Winsage

February 23, 2025

The Windows Concept Journey — ICS (Internet Connection Sharing)

Internet Connection Sharing (ICS) is a feature in Windows that allows a device with internet access to share its connection with other devices on a local area network (LAN). To enable or disable ICS, users can go to the Control Panel, access "Network Connections," right-click on the LAN or Wi-Fi device, select "Properties," click on the "Sharing" tab, and toggle the checkbox for "Allow other network users to connect through this computer’s Internet connection." ICS can also be configured using PowerShell or the netsh.exe command. It provides services such as DHCP and NAT and can share various connection types, including dial-up, PPPoE, and VPN. ICS has been integrated with UPnP since Windows XP for remote discovery and control. The settings for ICS are stored in the Windows registry at "HKLMSOFTWAREPoliciesMicrosoftWindowsNetwork Connections."