Fix: CDPUserSvc Has Stopped Working in Windows 10 / Windows Server 2016

After the installation of latest security updates on Windows 10 / Windows Server 2016, users began to complain about persistent failures of the CDPUserSvc service. In this post we’ll look at what the CDPUserSvc service is, why it periodically terminates unexpectedly, how to fix this problem and whether it is possible to disable this service in Windows 10 / Windows Server 2016.

Service CDPUserSvc first appeared in Windows 10, and from the very beginning it causes users a lot of questions and creates a number of problems.

Error: CDPUserSvc_xxxxx Has Stopped Working

Quite recently some Windows 10 / Windows Server 2016 users have started to complain about the following error that appeared at Windows startup, shutdown or even every few minutes:

In the application log, the error like this constantly appears:

On Windows 10 computers, some users reported this error after the installation of Anniversary Update (1607) or Fall Creators Update (1709). In this case, you should try to start the CDPUserSvc service in an isolated process or completely disable it (see below).

In most cases, this bug is caused by the November update KB4048953 update for Windows Server 2016 and Windows 10.

If you have this update installed, to get rid of the problem, it’s enough to correctly uninstall the KB4048953 update (wusa.exe /uninstall /kb:4048953) or wait for the next cumulative update package, in which the bug should be fixed.

What is the CDPUserSvc Service?

CDPUserSvc means Connected Devices Platform User Service. The full name of the service is dynamic and consists of the string CDPUserSvc_ and 5 randomly generated characters (in my example, it is CDPUserSvc_65bd2).

In different Windows 10 builds, CDPUserSvc has a different startup type:

• In Windows 10 1507 – manual startup;
• In 1511 the service is disabled;
• In 1607, 1703, 1709, 1803 – start type Automatic.

sc query| find "CDPUser"
sc query CDPUserSvc_65bd2

The service is started in the svchost process: svchost.exe -k UnistackSvcGroup

The executable is %WinDir%\System32\CDPSvc.dll

It is interesting that if you open the console with the list of services (Services.msc) and find CDPUserSvc, you’ll see that there is the following text in the description:

It is not clear why it happens.

I couldn’t find any official information from Microsoft about this service. If you analyze the CDPUserSvc connections, you can find that this service regularly connects to Microsoft and OneDrive servers and sends some data over HTTPS. Let’s see what the processes run in UnistackSvcGroup look like. To do it run Process Explorer, open svchost.exe properties and look at them.

Five services are running in this process (please, note that all of them contain the same 5-character identifier as CDPUserSvc):

• CDPUserSvc_xxxxx
• OneSyncSvc_xxxxx – is responsible for synchronization of mail, contacts, calendar and other user data;
• PimIndexMaintenanceSvc_xxxxx – is the contact indexing service for faster search;
• UnistoreSvc_xxxxx – stores structured user data (contacts, calendar, mail);
• UserDataSvc_xxxxx – provides access to the structured user data.

It is likely that CDPUserSvc is also responsible for synchronization of user data with MSFT servers. (Is it the telemetry? Do you really need it?) So CDPUserSvc may be disabled without any harm to your OS (of course, if you are not using native Windows 10 contacts, mail and calendar apps).

CDPUserSvc Isolation

Another solution that should fix the problem of constant CDPUserSvc_xxxxx service crash is running it in an isolated mode. To do it, run this command in the elevated command prompt:

sc config cdpusersvc type= own

After that CDPuserSvc will start in its own svchost.exe process. Check if the problem of CDPuserSvc failure persists. If it does, try to disable the service.

How to Disable CDPUserSvc Service

If you stop CDPUserSvc_6b511 manually and set it to Disabled in the Service Management (services.msc), it some time it will resume again (under another name).

You can disable the launch of this service in the registry. To do it, change the value of the Start parameter from 2 (Automatic startup) to 4 (Disabled) in the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CDPUserSvc.

Or run these commands:

sc config CDPUserSvc start= disabled
reg add "HKLM\SYSTEM\CurrentControlSet\Services\CDPUserSvc /v "Start" /t REG_DWORD /d "4" /f