Windows Mobile 6.5
A version of this page is also available for

This function creates a GUID, a unique 128-bit integer used for CLSIDs and interface identifiers.

HRESULT CoCreateGuid(
  GUID* pguid


[out] Pointer to the requested GUID on return.


The GUID was successfully created.

Microsoft Win32® errors are returned by UuidCreate but wrapped as an HRESULT.

The CoCreateGuid function calls the RPC function UuidCreate, which creates a GUID, a globally unique 128-bit integer.

Use the CoCreateGuid function when you need an absolutely unique number that you will use as a persistent identifier in a distributed environment.

To a very high degree of certainty, this function returns a unique value––no other invocation, on the same or any other system (networked or not), should return the same value.

To determine whether the platform supports this function, see Determining Supported COM APIs.

Windows Embedded CEWindows CE 3.0 and later
Windows MobileWindows Mobile Version 5.0 and later