What is the CDPUserSvc service?

It's part of Connected Devices Platform Service.

CDP Service itself says: This service is used for Connected Devices and Universal Glass scenarios.

The files are all c:\windows\system32\cdp*.dll:

cdp.dll
cdprt.dll
cdpusersvc.dll
cdprefernce.exe

Slightly more about that here: http://www.tenforums.com/general-support/58863-connected-devices-platform-service-what-does-do.html

I recommend reading the reference to the ZDNet Article on "Project Rome" in the link above.

If you use "strings" on the cdpusersvc.dll you will find references to Universal Glass and a few other backend bits.

If you want to disable the service, you can do so by modifying both the registry keys with the name:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CDPUserSvc

In both keys, modify the value Start from 2 to 4 and restart.

The reason it fails to read the description is actually because the service doesn't have a describer assigned to it. The services' description tag is empty so it's basically trying to read a description that is not there.

It should not effect it's ability to run and perform. Descriptions are for user's eyes only and have nothing to do with the actual functionality of the system.

It cannot be disabled because the service is a critical kernel-level service, just like how the RPC service is. Disabling it will cause core components to fail. It's also required for the settings app to function and any windows store apps that use wireless adapters (Bluetooth, NFC, etc) will fail to run. The service is deliberately locked by the Windows team to keep people from disabling the service and BSOD their PCs (I was able to remove most of the security around this service to disable it on a test machine. Each time it will blue screen when disabled).