Multi-User Win 10 image deployment fails Join to ARM AVD step

Here's the info from NMM for the erroring step:

Remove old extension, old result: {"name":"SYNC-AVD-5ba3-join-arm-wvd-ext","type":"Microsoft.Powershell.DSC","typeHandlerVersion":"2.80.3.0","substatuses":[{"code":"ComponentStatus/DscConfigurationLog/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"[2024-09-25 20:43:18Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ] [[Script]ExecuteRdAgentInstallClient]\r\n[2024-09-25 20:43:18Z] [VERBOSE] [SYNC-AVD-5ba3]: [[Script]ExecuteRdAgentInstallClient] Performing the operation \"Set-TargetResource\" on target \"Executing the SetScript with the user supplied credential\".\r\n[2024-09-25 20:43:27Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] [[Script]ExecuteRdAgentInstallClient] in 9.6100 seconds.\r\n[2024-09-25 20:43:28Z] [ERROR] PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. \r\n[2024-09-25 20:43:28Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ]\r\n[2024-09-25 20:43:28Z] [ERROR] The SendConfigurationApply function did not succeed.\r\n[2024-09-25 20:43:28Z] [VERBOSE] Operation 'Invoke CimMethod' complete.\r\n[2024-09-25 20:43:28Z] [VERBOSE] Time taken for configuration job to complete is 10.088 seconds\r\n[2024-09-25 20:44:30Z] [VERBOSE] Performing the operation \"Start-DscConfiguration: SendMetaConfigurationApply\" on target \"MSFT_DSCLocalConfigurationManager\".\r\n[2024-09-25 20:44:30Z] [VERBOSE] Perform operation 'Invoke CimMethod' with following parameters, ''methodName' = SendMetaConfigurationApply,'className' = MSFT_DSCLocalConfigurationManager,'namespaceName' = root/Microsoft/Windows/DesiredStateConfiguration'.\r\n[2024-09-25 20:44:30Z] [VERBOSE] An LCM method call arrived from computer SYNC-AVD-5ba3 with user sid S-1-5-18.\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ]\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Resource ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] [MSFT_DSCMetaConfiguration] in 0.0550 seconds.\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Resource ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ]\r\n[2024-09-25 20:44:30Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] in 0.1620 seconds.\r\n[2024-09-25 20:44:30Z] [VERBOSE] Set-DscLocalConfigurationManager finished in 0.417 seconds.\r\n[2024-09-25 20:44:30Z] [VERBOSE] Operation 'Invoke CimMethod' complete.","time":null},{"code":"ComponentStatus/DscExtensionLog/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"[2024-09-25 20:42:42Z] Creating Working directory: C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\r\n[2024-09-25 20:42:42Z] Downloading configuration package\r\n[2024-09-25 20:42:42Z] Downloading https://nmmstorageaccount.blob.core.windows.net/vm-extensions/ArmWvdClientSideSetup.4.9.zip to C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\ArmWvdClientSideSetup.4.9.zip\r\n[2024-09-25 20:43:10Z] Extracting ArmWvdClientSideSetup.4.9.zip\r\n[2024-09-25 20:43:10Z] Looking for the definition of the configuration function.\r\n[2024-09-25 20:43:10Z] Executing C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\Configuration.ps1\r\n[2024-09-25 20:43:10Z] Preparing configuration arguments and configuration data.\r\n[2024-09-25 20:43:10Z] Creating MOF files.\r\n[2024-09-25 20:43:10Z] Executing the configuration function to generate the MOF files.\r\n[2024-09-25 20:43:12Z] Verifying metaconfiguration for reboot information...\r\n[2024-09-25 20:43:12Z] Backing up C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\AdditionalSessionHosts\\localhost.meta.mof\r\n[2024-09-25 20:43:12Z] No match for RegistrationKey found in the meta mof file\r\n[2024-09-25 20:43:12Z] WMF 5 or newer, Injecting RebootNodeIfNeeded = False and ActionAfterReboot = \"StopConfiguration\"\r\n[2024-09-25 20:43:12Z] Executing Set-DscLocalConfigurationManager...\r\n[2024-09-25 20:43:13Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:43:16Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:43:16Z] Get-DscLocalConfigurationManager: \r\n\r\nActionAfterReboot : StopConfiguration\r\nAgentId : 04992463-7B7A-11EF-8F4C-0022487E7992\r\nAllowModuleOverWrite : False\r\nCertificateID : \r\nConfigurationDownloadManagers : {}\r\nConfigurationID : \r\nConfigurationMode : ApplyOnly\r\nConfigurationModeFrequencyMins : 15\r\nCredential : \r\nDebugMode : {NONE}\r\nDownloadManagerCustomData : \r\nDownloadManagerName : \r\nLCMCompatibleVersions : {1.0, 2.0}\r\nLCMState : PendingConfiguration\r\nLCMStateDetail : \r\nLCMVersion : 2.0\r\nStatusRetentionTimeInDays : 10\r\nSignatureValidationPolicy : NONE\r\nSignatureValidations : {}\r\nMaximumDownloadSizeMB : 500\r\nPartialConfigurations : \r\nRebootNodeIfNeeded : False\r\nRefreshFrequencyMins : 30\r\nRefreshMode : PUSH\r\nReportManagers : {}\r\nResourceModuleManagers : {}\r\nPSComputerName : \r\n\r\n\r\n\r\n\r\n[2024-09-25 20:43:16Z] Executing Start-DscConfiguration...\r\n[2024-09-25 20:43:17Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:43:29Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:43:29Z] Updating execution status (HKLM:\\SOFTWARE\\Microsoft\\Azure\\DSC\\2.80.3.0\\Status)\r\n[2024-09-25 20:43:29Z] LCM state is PendingConfiguration\r\n[2024-09-25 20:44:29Z] DSC configuration completed.\r\n[2024-09-25 20:44:29Z] Resetting metaconfiguration...\r\n[2024-09-25 20:44:29Z] Restoring C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\AdditionalSessionHosts\\localhost.meta.mof.bk...\r\n[2024-09-25 20:44:29Z] Executing Set-DscLocalConfigurationManager...\r\n[2024-09-25 20:44:29Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:44:31Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:44:32Z] Get-DscLocalConfigurationManager: \r\n\r\nActionAfterReboot : ContinueConfiguration\r\nAgentId : 04992463-7B7A-11EF-8F4C-0022487E7992\r\nAllowModuleOverWrite : False\r\nCertificateID : \r\nConfigurationDownloadManagers : {}\r\nConfigurationID : \r\nConfigurationMode : ApplyOnly\r\nConfigurationModeFrequencyMins : 15\r\nCredential : \r\nDebugMode : {NONE}\r\nDownloadManagerCustomData : \r\nDownloadManagerName : \r\nLCMCompatibleVersions : {1.0, 2.0}\r\nLCMState : PendingConfiguration\r\nLCMStateDetail : \r\nLCMVersion : 2.0\r\nStatusRetentionTimeInDays : 10\r\nSignatureValidationPolicy : NONE\r\nSignatureValidations : {}\r\nMaximumDownloadSizeMB : 500\r\nPartialConfigurations : \r\nRebootNodeIfNeeded : True\r\nRefreshFrequencyMins : 30\r\nRefreshMode : PUSH\r\nReportManagers : {}\r\nResourceModuleManagers : {}\r\nPSComputerName : \r\n\r\n\r\n\r\n\r\n[2024-09-25 20:44:32Z] Settings handler status to 'error' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)","time":null},{"code":"ComponentStatus/Metadata/succeeded","level":"Info","displayStatus":"Provisioning succeeded","message":"VMUUId=D47AC356-F332-4B4F-B971-F72B65E6F085;AgentId=04992463-7B7A-11EF-8F4C-0022487E7992;","time":null}],"statuses":[{"code":"ProvisioningState/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"DSC Configuration 'AdditionalSessionHosts' completed with error(s). Following are the first few: PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. The SendConfigurationApply function did not succeed.","time":"2024-09-25T20:44:32Z"}]}
Extension was removed
Install Join ARM AVD extension
Error: An error occurred during Join ARM WVD extension installation: System.AggregateException: One or more errors occurred. (Long running operation failed with status 'Failed'. Additional Info:'VM has reported a failure when processing extension 'SYNC-AVD-5ba3-join-arm-wvd-ext' (publisher 'Microsoft.Powershell' and type 'DSC'). Error message: 'DSC Configuration 'AdditionalSessionHosts' completed with error(s). Following are the first few: PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. The SendConfigurationApply function did not succeed.'. More information on troubleshooting is available at https://aka.ms/VMExtensionDSCWindowsTroubleshoot. ') ---> Microsoft.Rest.Azure.CloudException: Long running operation failed with status 'Failed'. Additional Info:'VM has reported a failure when processing extension 'SYNC-AVD-5ba3-join-arm-wvd-ext' (publisher 'Microsoft.Powershell' and type 'DSC'). Error message: 'DSC Configuration 'AdditionalSessionHosts' completed with error(s). Following are the first few: PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. The SendConfigurationApply function did not succeed.'. More information on troubleshooting is available at https://aka.ms/VMExtensionDSCWindowsTroubleshoot. ' at Microsoft.Rest.ClientRuntime.Azure.LRO.AzureLRO`2.CheckForErrors() at Microsoft.Rest.ClientRuntime.Azure.LRO.PutLRO`2.CheckForErrors() at Microsoft.Rest.ClientRuntime.Azure.LRO.AzureLRO`2.StartPollingAsync() at Microsoft.Rest.ClientRuntime.Azure.LRO.AzureLRO`2.BeginLROAsync() at Microsoft.Rest.Azure.AzureClientExtensions.GetLongRunningOperationResultAsync[TBody,THeader](IAzureClient client, AzureOperationResponse`2 response, Dictionary`2 customHeaders, CancellationToken cancellationToken) at Microsoft.Rest.Azure.AzureClientExtensions.GetLongRunningOperationResultAsync[TBody](IAzureClient client, AzureOperationResponse`1 response, Dictionary`2 customHeaders, CancellationToken cancellationToken) at Microsoft.Rest.Azure.AzureClientExtensions.GetPutOrPatchOperationResultAsync[TBody](IAzureClient client, AzureOperationResponse`1 response, Dictionary`2 customHeaders, CancellationToken cancellationToken) at Microsoft.Azure.Management.Compute.Fluent.VirtualMachineExtensionsOperations.CreateOrUpdateWithHttpMessagesAsync(String resourceGroupName, String vmName, String vmExtensionName, VirtualMachineExtensionInner extensionParameters, Dictionary`2 customHeaders, CancellationToken cancellationToken) at Microsoft.Azure.Management.Compute.Fluent.VirtualMachineExtensionsOperationsExtensions.CreateOrUpdateAsync(IVirtualMachineExtensionsOperations operations, String resourceGroupName, String vmName, String vmExtensionName, VirtualMachineExtensionInner extensionParameters, CancellationToken cancellationToken) at Microsoft.Azure.Management.Compute.Fluent.VirtualMachineExtensionImpl.CreateAsync(CancellationToken cancellationToken) --- End of inner exception stack trace --- at Microsoft.Azure.Management.Compute.Fluent.VirtualMachineImpl.CreateResourceAsync(CancellationToken cancellationToken) at Microsoft.Azure.Management.ResourceManager.Fluent.Core.ResourceActions.Creatable`4.Microsoft.Azure.Management.ResourceManager.Fluent.Core.ResourceActions.IResourceCreator<IResourceT>.CreateResourceAsync(CancellationToken cancellationToken) at Microsoft.Azure.Management.ResourceManager.Fluent.Core.DAG.CreatorTaskItem`1.ExecuteAsync(CancellationToken cancellationToken) at Microsoft.Azure.Management.ResourceManager.Fluent.Core.DAG.TaskGroupBase`1.ExecuteNodeTaskAsync(DAGNode`1 node, CancellationToken cancellationToken) at Microsoft.Azure.Management.ResourceManager.Fluent.Core.ResourceActions.CreatableUpdatable`5.ApplyAsync(CancellationToken cancellationToken, Boolean multiThreaded) at Riviere.Provision.Jobs.Partials.VMExtensions.JoinArmWvdExtension.AddTo(IVirtualMachine vm, String registrationToken) in D:\a\1\s\src\Riviere.Provision\Jobs\Partials\VMExtensions\JoinArmWvdExtension.cs:line 62 at Riviere.Provision.Jobs.Partials.VMExtensions.JoinArmWvdExtension.InstallTo(IVirtualMachine vm, String registrationToken, JobDetailsStringBuilder logger) in D:\a\1\s\src\Riviere.Provision\Jobs\Partials\VMExtensions\JoinArmWvdExtension.cs:line 49. With extension result: {"name":"SYNC-AVD-5ba3-join-arm-wvd-ext","type":"Microsoft.Powershell.DSC","typeHandlerVersion":"2.80.3.0","substatuses":[{"code":"ComponentStatus/DscConfigurationLog/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"[2024-09-25 20:58:25Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ] [[Script]ExecuteRdAgentInstallClient]\r\n[2024-09-25 20:58:25Z] [VERBOSE] [SYNC-AVD-5ba3]: [[Script]ExecuteRdAgentInstallClient] Performing the operation \"Set-TargetResource\" on target \"Executing the SetScript with the user supplied credential\".\r\n[2024-09-25 20:58:35Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] [[Script]ExecuteRdAgentInstallClient] in 9.6720 seconds.\r\n[2024-09-25 20:58:35Z] [ERROR] PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. \r\n[2024-09-25 20:58:35Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ]\r\n[2024-09-25 20:58:35Z] [ERROR] The SendConfigurationApply function did not succeed.\r\n[2024-09-25 20:58:35Z] [VERBOSE] Operation 'Invoke CimMethod' complete.\r\n[2024-09-25 20:58:35Z] [VERBOSE] Time taken for configuration job to complete is 10.154 seconds\r\n[2024-09-25 20:59:39Z] [VERBOSE] Performing the operation \"Start-DscConfiguration: SendMetaConfigurationApply\" on target \"MSFT_DSCLocalConfigurationManager\".\r\n[2024-09-25 20:59:39Z] [VERBOSE] Perform operation 'Invoke CimMethod' with following parameters, ''methodName' = SendMetaConfigurationApply,'className' = MSFT_DSCLocalConfigurationManager,'namespaceName' = root/Microsoft/Windows/DesiredStateConfiguration'.\r\n[2024-09-25 20:59:39Z] [VERBOSE] An LCM method call arrived from computer SYNC-AVD-5ba3 with user sid S-1-5-18.\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ]\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Resource ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ Start Set ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] [MSFT_DSCMetaConfiguration] in 0.0890 seconds.\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Resource ] [MSFT_DSCMetaConfiguration]\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ]\r\n[2024-09-25 20:59:39Z] [VERBOSE] [SYNC-AVD-5ba3]: LCM: [ End Set ] in 0.2750 seconds.\r\n[2024-09-25 20:59:39Z] [VERBOSE] Operation 'Invoke CimMethod' complete.\r\n[2024-09-25 20:59:39Z] [VERBOSE] Set-DscLocalConfigurationManager finished in 0.486 seconds.","time":null},{"code":"ComponentStatus/DscExtensionLog/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"[2024-09-25 20:57:50Z] Creating Working directory: C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\r\n[2024-09-25 20:57:50Z] Downloading configuration package\r\n[2024-09-25 20:57:50Z] Downloading https://nmmstorageaccount.blob.core.windows.net/vm-extensions/ArmWvdClientSideSetup.4.9.zip to C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\ArmWvdClientSideSetup.4.9.zip\r\n[2024-09-25 20:58:17Z] Extracting ArmWvdClientSideSetup.4.9.zip\r\n[2024-09-25 20:58:18Z] Looking for the definition of the configuration function.\r\n[2024-09-25 20:58:18Z] Executing C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\bin\\..\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\Configuration.ps1\r\n[2024-09-25 20:58:18Z] Preparing configuration arguments and configuration data.\r\n[2024-09-25 20:58:18Z] Creating MOF files.\r\n[2024-09-25 20:58:18Z] Executing the configuration function to generate the MOF files.\r\n[2024-09-25 20:58:20Z] Verifying metaconfiguration for reboot information...\r\n[2024-09-25 20:58:20Z] Backing up C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\AdditionalSessionHosts\\localhost.meta.mof\r\n[2024-09-25 20:58:20Z] No match for RegistrationKey found in the meta mof file\r\n[2024-09-25 20:58:20Z] WMF 5 or newer, Injecting RebootNodeIfNeeded = False and ActionAfterReboot = \"StopConfiguration\"\r\n[2024-09-25 20:58:20Z] Executing Set-DscLocalConfigurationManager...\r\n[2024-09-25 20:58:21Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:58:23Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:58:24Z] Get-DscLocalConfigurationManager: \r\n\r\nActionAfterReboot : StopConfiguration\r\nAgentId : 04992463-7B7A-11EF-8F4C-0022487E7992\r\nAllowModuleOverWrite : False\r\nCertificateID : \r\nConfigurationDownloadManagers : {}\r\nConfigurationID : \r\nConfigurationMode : ApplyOnly\r\nConfigurationModeFrequencyMins : 15\r\nCredential : \r\nDebugMode : {NONE}\r\nDownloadManagerCustomData : \r\nDownloadManagerName : \r\nLCMCompatibleVersions : {1.0, 2.0}\r\nLCMState : PendingConfiguration\r\nLCMStateDetail : \r\nLCMVersion : 2.0\r\nStatusRetentionTimeInDays : 10\r\nSignatureValidationPolicy : NONE\r\nSignatureValidations : {}\r\nMaximumDownloadSizeMB : 500\r\nPartialConfigurations : \r\nRebootNodeIfNeeded : False\r\nRefreshFrequencyMins : 30\r\nRefreshMode : PUSH\r\nReportManagers : {}\r\nResourceModuleManagers : {}\r\nPSComputerName : \r\n\r\n\r\n\r\n\r\n[2024-09-25 20:58:24Z] Executing Start-DscConfiguration...\r\n[2024-09-25 20:58:24Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:58:36Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:58:36Z] Updating execution status (HKLM:\\SOFTWARE\\Microsoft\\Azure\\DSC\\2.80.3.0\\Status)\r\n[2024-09-25 20:58:36Z] LCM state is PendingConfiguration\r\n[2024-09-25 20:59:36Z] DSC configuration completed.\r\n[2024-09-25 20:59:36Z] Resetting metaconfiguration...\r\n[2024-09-25 20:59:36Z] Restoring C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\DSCWork\\ArmWvdClientSideSetup.4.9.0\\AdditionalSessionHosts\\localhost.meta.mof.bk...\r\n[2024-09-25 20:59:36Z] Executing Set-DscLocalConfigurationManager...\r\n[2024-09-25 20:59:36Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:59:40Z] Settings handler status to 'transitioning' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)\r\n[2024-09-25 20:59:41Z] Get-DscLocalConfigurationManager: \r\n\r\nActionAfterReboot : ContinueConfiguration\r\nAgentId : 04992463-7B7A-11EF-8F4C-0022487E7992\r\nAllowModuleOverWrite : False\r\nCertificateID : \r\nConfigurationDownloadManagers : {}\r\nConfigurationID : \r\nConfigurationMode : ApplyOnly\r\nConfigurationModeFrequencyMins : 15\r\nCredential : \r\nDebugMode : {NONE}\r\nDownloadManagerCustomData : \r\nDownloadManagerName : \r\nLCMCompatibleVersions : {1.0, 2.0}\r\nLCMState : PendingConfiguration\r\nLCMStateDetail : \r\nLCMVersion : 2.0\r\nStatusRetentionTimeInDays : 10\r\nSignatureValidationPolicy : NONE\r\nSignatureValidations : {}\r\nMaximumDownloadSizeMB : 500\r\nPartialConfigurations : \r\nRebootNodeIfNeeded : True\r\nRefreshFrequencyMins : 30\r\nRefreshMode : PUSH\r\nReportManagers : {}\r\nResourceModuleManagers : {}\r\nPSComputerName : \r\n\r\n\r\n\r\n\r\n[2024-09-25 20:59:41Z] Settings handler status to 'error' (C:\\Packages\\Plugins\\Microsoft.Powershell.DSC\\2.80.3.0\\Status\\0.status)","time":null},{"code":"ComponentStatus/Metadata/succeeded","level":"Info","displayStatus":"Provisioning succeeded","message":"VMUUId=D47AC356-F332-4B4F-B971-F72B65E6F085;AgentId=04992463-7B7A-11EF-8F4C-0022487E7992;","time":null}],"statuses":[{"code":"ProvisioningState/failed/8","level":"Error","displayStatus":"Provisioning failed","message":"DSC Configuration 'AdditionalSessionHosts' completed with error(s). Following are the first few: PowerShell DSC resource MSFT_ScriptResource failed to execute Set-TargetResource functionality with error message: Specified cast is not valid. The SendConfigurationApply function did not succeed.","time":"2024-09-25T20:59:41Z"}]}

Randy, is it possible that one of those images has the AVD agent already installed on the source VM?  This is a common cause of this.  You'll find that during the image creation/import process that this is enabled by default here for this reason:

No, the AVD agent has never been installed on the images. I double checked that it is not currently installed and there is no RDagentBootLoader, RDInfraAgent or RDMonitoringAgent records in the Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft registry location.

I would say that it's something wrong with the image.
You could try installing the AVD Agent on the host (see NMM-SE/Azure Runbooks/Reinstall AVD Agent.ps1 at main · Get-Nerdio/NMM-SE (github.com)) , and then uninstalling it before doing the "Set as Image" task.

If that doesn't work, you can always open a support ticket and our MSP Escalations Team can help you out.

Thanks for the idea. It didn't work. I'll be starting over with a fresh image.

Bummer.
I was hoping that would fix it.
Oh, well. A fresh image is always a good alternative. 🙂