Being able to auto-configure your target is not necessary to debug it. In Multi-ICE Server you can load a manual configuration file that tells Multi-ICE the devices connected in the JTAG chain. Similarly, you can define your target manually in RVConfig.

During auto-configuration, the JTAG tool reads the TAP ID code of the core via JTAG. In most cases this information alone is not enough to know the type and revision of the core, so the JTAG tool usually needs to stop the core and read the CP15 ID code register. If this operation fails, then auto-configuration is not correctly completed and the core is not detected.

When the debugger connects to the target via the JTAG tool, it usually tries to put it in debug state. If it fails to do this, the debugger reports an error.

Therefore, if auto-configuration fails it is likely that the debugger will not be able to connect to the target.

The errors raised by Multi-ICE server and the debugger when connecting to the core are explained in the troubleshooting sections of the Multi-ICE v2.2 User Guide.