Configuration Manager manifest synchronization failing since 8 July 2026
Has anyone else experienced Configuration Manager Updates and Servicing synchronization failures since 8 July 2026? We have three independent Microsoft Configuration Manager hierarchies: Test environment Production T0 environment Production T1 environment All three started showing the same SMS_DMP_DOWNLOADER error during the last three days. The affected request is sent to: https://sccm.manage.microsoft.com/SCCMConnectedService.svc/Manifest Configuration Manager builds a hierarchy-specific request containing the Tenant, Version, Ring, and Branch parameters. However, the endpoint now returns only: OK The resulting file is: ConfigMgr.Update.Manifest.cab Size: 2 bytes Hex: 4F 4B Content: OK Because this is not a valid signed CAB file, dmpdownloader.log records: manifest.cab (http response) size is 2 Error in verifying the trust of file ConfigMgr.Update.Manifest.cab' WARNING: Failed to call IsFileTrusted WARNING: Failed to download and verify the manifest.cab. We cant get info in Updates and Servicing mode.
Existing required application deployments policy is not sent to devices
I have couple hundred applications in SCCM/MCM that are set to required and whenever there is a new device is built, all these required applications automatically get installed. I am on 2503 and 5 days ago i started seeing this issue. But if modify that deployment with current date and time then the application gets deployed right away if i run Application Deployment evaluation cycle. I also tested by deleting the existing deployment and created a new required deployment and run Application Deployment evaluation cycle then the application installs right away. The problem seems like the Primary server is not sending the policy to the client for existing deployments. The application compliance that we see for every deployment under Monitoring for all the devices moved to Error with Success. Not sure why this is happening. All these changes i noticed in the last one week. A week ago all these Already Compliant and Success status device count is under Success tab. Let me know if you have any suggestions.
Updates Not Installing by Install Deadline
Hello all! We have an organization with about 12,000 Windows 11 Workstations. I'm noticing that even though install deadline is set, and updates are allowed to be installed before install deadline hits, we are noticing in Software Center that updates say "will install after _____" (deadline date). How can I change this? I want updates to install during the maintenance window as well as a reboot. What am I missing? Connor
SCCM PXE Boot Deep Dive – Backend Flow & DP Migration
SCCM PXE Boot Deep Dive – Backend Flow & DP Migration I recently worked on a Distribution Point migration and noticed PXE requests were still routing to the old DP due to DHCP/IP helper configuration. I put together a deep dive explaining: PXE flow (DHCP and TFTP sequence) Role of Distribution Points What changes during DP migration Common failure points One key takeaway: PXE issues are almost always network and routing related, not SCCM itself. Curious how others are handling PXE in large environments. Are you standardizing on IP helpers or still using DHCP options? Full article: http://SCCM%20PXE%20Boot%20Deep%20Dive%20–%20Backend%20Flow%20&%20DP%20MigrationMECM OSD TS Application Installations fail randomly to download content.
We are experiencing a persistent and well-documented issue with MECM OSD Task Sequences where Applications randomly fail to install after the MECM client has been installed. This behavior seems to affect many environments and has been an ongoing problem for years, yet a definitive solution remains elusive. In our case, we have over 30 Applications included in the OSD Task Sequence. Despite implementing all commonly recommended mitigations—such as inserting an additional restart after the MECM client installation and including a two-minute delay before the Application install task group begins—we still encounter random failures. The issue is not limited to any specific Application; it can be any one of the 30+ Apps, and the failure to download appears to occur entirely at random. Occasionally, most of the Applications install successfully, and only one will fail, which subsequently causes the entire Task Sequence to fail with the same error. Importantly, all of these Applications install without any issues post-OSD, further confirming that the problem lies not with the Applications themselves but with the process during the Task Sequence. The randomness of which App fails also suggests an underlying process, feature, or timing issue—not an App configuration problem. We have thoroughly validated all related infrastructure settings: Boundaries and boundary groups have been triple-checked. No boundary is assigned to multiple groups. Site system assignments are correct. We are using PKI certificates and HTTPS, and the client authentication certificate is present on the device at the time of failure. The issue has been replicated across both Windows 10 and Windows 11, ruling out any specific cumulative updates or OS version anomalies. No additional language packs are being installed—only language fallback is applied via the "Apply Windows Settings" step. One suspicious observation is the lack of any reference to our local Distribution Point in the LocationServices or CAS logs during failure events. Initially, this pointed to a possible boundary misconfiguration, but after multiple checks, no issues have been identified. Unfortunately, we are unable to use the common workaround of converting Applications to Packages, due to internal policies and deployment requirements. Therefore, we need to resolve this while continuing to use Applications in the Task Sequence. Given the number of years this issue has persisted across customer environments, it's surprising there isn’t more formal guidance or documentation available to help isolate the root cause. If anyone has encountered a similar scenario or has any advanced troubleshooting tips, we would greatly appreciate your insight.SCCM - 23/24H2 to 25H2 Upgrade
Hello SCCM Community! Having an issue with upgrading devices from 23 and 24H2 to 25H2, I am downloading the newest version in SCCM under Windows Servicing and Feature Upgrades and deploying it to the targeted collection, but nothing shows in Software Center. Upon checking the UpdatesDeployment log, it shows Actionable Updates = 0 in one of the lines, but I'm wondering why WUA is determining updates do not apply to the machine. I believed this could be a GPO restriction but I've confirmed that there are no conflicting GPOs or Registry Edits. Any suggestions? Thanks!
SYSTEM CENTER IMPLEMENTATION & LICENSING Guide
Dear Microsoft Community, Our organization is planning to deploy a comprehensive IT management solution using the Microsoft System Center Suite. The goal is to streamline infrastructure operations, enhance backup and recovery, manage both virtual and physical resources, oversee endpoints, and maintain security and compliance. We need guidance regarding the number and type of licenses required, specifically Client Management Licenses (CML), Server Management Licenses (ML), and System Center Suite licenses.Can't find and delete an antivirus exclusion made in MECM.
In the Microsoft Endpoint Configuration Manager current brunch I've added some of the detected malware to exclusions list via right-click in the section "Monitoring-Security-Endpoint protection status - Malware detected" and "Allow this threat". They were excluded for all the computers in a collection. How and where to find this exclusions and delete them? They are appeared on the client computers but not in the MECM Antimalware policies.Using REST API to get / set device variables
Hi, I'm trying to set a couple of variables against a machine name, through using the REST API. These are the variables that are set that you can see in the console if you right click properties on a device and go to the 'Variables' tab. These are handy because they can later be referenced during Task Sequences / OSD. I just can't figure out how to do it with the REST API. I have no issues doing it with the powershell module using the 'New-CMDeviceVariable' command, but my solution i'm building at the moment requires the solution to be done with rest api, not with ps modules... I can connect to REST API using powershell using commands such as the below. This all works fine. $ConfigMgrServerURL = "https://SCCMserver.domain.local" $MachineName = "MachineName1" # Following command is a sample GET request, which works. (Invoke-RestMethod -Method Get -Uri "$ConfigMgrServerURL/AdminService/wmi/SMS_R_System?`$filter=Name eq '$MachineName'" -Credential $Credential) #I can also fetch "Custom Properties" via this command (Invoke-RestMethod -Method Get -Uri "$ConfigMgrServerURL/AdminService/v1.0/Device($ResourceID)/AdminService.GetExtensionData" -Credential $Credential) Now i just can't see where i can go to set a variable on the machine. Does anyone have any ideas ? Thanks!Win11 24H2 slow to restart TS task execution following reboot task in bare metal OS deployment
When comparing OS deployment bare metal task sequence times between Windows 11 24H2 and Windows 10 22H2 I could see that 24H2 was considerably slower even though the task sequences were almost identical other than the OS being laid down on the device. I did a timing comparison and noticed two things in particularly that were taking considerably longer on the 24H2 device: 1) reboot tasks 2) time to finish up the task sequence work after the last step. For reboot tasks, I can see that the delay is between these two events in the SMSTS.log log: Waiting for policy to be compiled in 'root\ccm\policy\machine' namespace and Policy verification done within the OSDSetupHook component. On the Windows 10 device the time between those log entries was 1 second, but on Windows 11 24H2 those log entries vary, but it's usually around 2 minutes. At the end of the task sequence, after executing the last task, following The task execution engine successfully completed the current task sequence step smsts.log entry to when the smsts.log stops being written to, it takes 14 seconds for the Windows 10 device, but it takes 4:29 seconds for the Windows 11 device. The delays are similar, between these two events in SMSTS.log (see attached screen shot): End Task Sequence policy cleanup and Policy evaluation initiated within the TSManager component. Any reason policy work should take considerably longer on Win11 24H2? Any suggestions on where I can look to see as to why it's taking such a longer time to deal with policy work in 24H2? Is this a Win11 24H2 issue, a ConfigMan issue, or ConfigMan configuration issue? I am welcome to entertain any thoughts or suggestions folks have. Anyone else seeing this issue in their environment? Environment details: CM 2503 (5.0.9135.1000) without KB33177653 or KB34503790 installed. Windows 11 = 24H2 customized reference image built from August 2025 ISO. ADK = 21H2 (10.1.22000.1).
