dism.exe says the source file can't be found, not clear on what source file it's talking about

I'm running dism to try to fix my Windows 10 x64 laptop.

C:\WINDOWS\system32>dism.exe /online /cleanup-image /restorehealth

I'm getting the following error:

Deployment Image Servicing and Management tool
Version: 10.0.10586.0

Image Version: 10.0.10586.0

[==========================100.0%==========================]

Error: 0x800f081f

The source files could not be found.
Use the "Source" option to specify the location of the files that are required to restore the feature. For more information on specifying a source location, see http://go.microsoft.com/fwlink/?LinkId=243077.

The DISM log file can be found at C:\WINDOWS\Logs\DISM\dism.log

If I open the dism.log file I see the following:

2016-09-12 21:34:11, Info                  DISM   DISM.EXE: Succesfully registered commands for the provider: Edition Manager.
2016-09-12 21:34:11, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Getting Provider DISM Package Manager - CDISMProviderStore::GetProvider
2016-09-12 21:34:11, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Provider has previously been initialized.  Returning the existing instance. - CDISMProviderStore::Internal_GetProvider
2016-09-12 21:34:11, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 Processing the top level command token(cleanup-image). - CPackageManagerCLIHandler::Private_ValidateCmdLine
2016-09-12 21:34:11, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 Attempting to route to appropriate command handler. - CPackageManagerCLIHandler::ExecuteCmdLine
2016-09-12 21:34:11, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 Routing the command... - CPackageManagerCLIHandler::ExecuteCmdLine
2016-09-12 21:34:11, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 CBS session options=0x48100! - CDISMPackageManager::Internal_Finalize
2016-09-12 21:49:39, Info                  DISM   DISM Package Manager: PID=18504 TID=3432  Error in operation: source for package or file not found, ResolveSource() unsuccessful. (CBS HRESULT=0x800f081f) - CCbsConUIHandler::Error
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 Failed finalizing changes. - CDISMPackageManager::Internal_Finalize(hr:0x800f081f)
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 The source files could not be found; their location must be specified using the /source option to restore the feature. - GetCbsErrorMsg
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 Failed processing package changes with session option CbsSessionOptionRepairStoreCorruption - CDISMPackageManager::RestoreHealth(hr:0x800f081f)
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 The source files could not be found; their location must be specified using the /source option to restore the feature. - GetCbsErrorMsg
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 Failed to restore the image health. - CPackageManagerCLIHandler::ProcessCmdLine_CleanupImage(hr:0x800f081f)
2016-09-12 21:49:39, Error                 DISM   DISM Package Manager: PID=18504 TID=5968 Failed while processing command cleanup-image. - CPackageManagerCLIHandler::ExecuteCmdLine(hr:0x800f081f)
2016-09-12 21:49:39, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 Further logs for online package and feature related operations can be found at %WINDIR%\logs\CBS\cbs.log - CPackageManagerCLIHandler::ExecuteCmdLine
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Found the OSServices.  Waiting to finalize it until all other providers are unloaded. - CDISMProviderStore::Final_OnDisconnect
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Found the OSServices.  Waiting to finalize it until all other providers are unloaded. - CDISMProviderStore::Final_OnDisconnect
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Found the PE Provider.  Waiting to finalize it until all other providers are unloaded. - CDISMProviderStore::Final_OnDisconnect
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Finalizing the servicing provider(DISM Package Manager) - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Package Manager: PID=18504 TID=5968 Finalizing CBS core. - CDISMPackageManager::Finalize
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Disconnecting Provider: DISM Package Manager - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Finalizing the servicing provider(MsiManager) - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Disconnecting Provider: MsiManager - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Finalizing the servicing provider(IntlManager) - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Disconnecting Provider: IntlManager - CDISMProviderStore::Internal_DisconnectProvider
2016-09-12 21:49:39, Info                  DISM   DISM Provider Store: PID=18504 TID=5968 Finalizing the servicing provider(IBSManager) - CDISMProviderStore::Internal_DisconnectProvider

I see it saying it can't find the source, but I can't figure out what file it's trying to restore.

I tried adding a /source=f:\sources where f:\ points to an iso image of Windows 10, but it didn't help.

I got a Windows Update last night. I reran dism.exe /online /cleanup-image /restorehealth this morning and it ran with no errors. I guess the update fixed it.