# S03038 {#s03038}

## Error Code {#error_code .section}

S03038

## Error Message {#error_message .section}

`Invalid engine. RefId: S03038`

## Probable Causes {#probable_causes .section}

This error occurs when the first parameter of the `appendEvent` function is not the engine object returned by `createCEPEngine` or `streamEventSerializer`.

## Solutions {#solutions .section}

Check whether the engine name or handle is correct, or whether the engine exists.

**Parent topic:**[Error Code Reference](../../Troubleshooting/ErrorCode.md)

