Technet Article: https://docs.microsoft.com/en-us/mem/configmgr/develop/reference/core/clients/client-classes/triggerschedule-method-in-class-sms_client

The SCCM client allows for using PowerShell to trigger a SCCM Client update.

Example:

Hardware Inventory:
Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000001}"

Software Inventory:
Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000002}"

Machine Policy Retrieval and Evaluation
Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000022}"

Use Cases:

Silent install or uninstall string followed by a software inventory to update the database
msiexec /x <PRODUCT CODE> /qn
Remove-Item <Registry Keys> -Force
Remove-Item <Folder> -Force
powershell.exe Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000002}"

Patching a system with quicker reporting
msiexec /p <MSP file> /qn
powershell.exe Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000002}"

Standard BIOS Task sequence with a hardware update at the end for reporting to SCCM the updated hardware/bios information
Disable MBAM
Install BIOS package
powershell.exe Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000001}"

Get the latest software
Machine Policy Retrieval and Evaluation
Invoke-WMIMethod -Namespace root\ccm -Class SMS_CLIENT -Name TriggerSchedule "{00000000-0000-0000-0000-000000000022}"

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