DCOM Errors

The following error codes are typical HRESULTs you may get back from your client program. I've included some suggestions about what they

might mean. I've included the symbolic name, as well as the translated message text. This is by no means a comprehensive list, but it's a

great starting point for the most common errors.

CO_E_BAD_SERVER_NAME

A remote activation was necessary but the server

name provided was invalid.

This is one of the few self-explanatory error messages. Note that it doesn't mean

you entered the wrong server name. It means you entered an invalid server name.

Check that the name is in the proper network format - check for invalid characters.

Unresolved or non-existent servers show up with a different error message:

RPC_S_SERVER_UNAVAILABLE.

CO_E_SERVER_EXEC_FAILURE

Server execution failed.

Check the COM security FAQ for more information.

Microsoft Support - Article Q158508

(This site requires registration.)

E_ACCESSDENIED

General access denied error.

This is an error from the security subsystem. The server system rejected a

connection. These problems can be very difficult to diagnose. This error is most

likely when using DCOM for remote connections.

Check for activation problems, especially on Windows 95/98.

Check security settings with DCOMCNFG.

Reinstall the server and the Proxy/Stub DLL.

Be sure you have File/Print sharing enabled.

E_FAIL

Unspecified error.

This is often an application-specific error caused by a method returning E_FAIL.

E_NOINTERFACE

No such interface supported.

You asked a server for an interface it doesn't support. This means your CLSID is

probably OK, but the IID is not. This call is returned by QueryInterface (or through

CoCreateInstance) when it doesn't recognize an interface. It may also be a

proxy/stub problem.

This may be a registration problem. Try re-registering the server and proxy/stub.

E_OUTOFMEMORY

Ran out of memory.

This message may be unrelated to the actual error. See the security FAQ for some

other possibilities.

Microsoft Support - Article Q158508 (This site requires registration.)

ERROR_INVALID_PARAMETER

The parameter is incorrect.

You have a problem in one of the parameters to your function call. This is

commonly seen in functions such as CoCreateInstance, CoCreateInstanceEx,

CoInitializeSecurity, etc.

ERROR_SUCCESS

The operation completed successfully.

The same message as S_OK and NO_ERROR.

REGDB_E_CLASSNOTREG

Class Not Registered.

A registration or CLSID problem. Check your GUIDs.

The server may not be running on the remote Windows 95/98 system.

http://devcentral.iticentral.com/articles/DCOM/intro_DCOM/part3/default.php (10 of 11) [7/9/2001 2:53:01 PM]

DevCentral - Understanding DCOM - Part III

RPC_S_SERVER_UNAVAILABLE

RPC Server is unavailable.

This problem is very common when working with remote servers. This is a generic

remote connection error. RPC is the protocol used to implement DCOM. This can be

a system setup problem or a security problem. You're about to learn a lot about

networking!

You may be trying to connect to an incorrect or disconnected computer. Check the

server name.

Be sure DCOM and RPC are enabled on the computer. Use DCOMCNFG or OLEVIEW

(in "System Configuration" under the File menu).

Re-register the server and proxy/stub.

Check server activation problems, especially on Window 95/98.

Try all the steps defined in the previous section.