## -903: Hostfile I/O error

### Explanation:

An error occurred while operating a command file or host file or a backup device.

### User Action:

The error message contains an additional error description which must be interpreted according to the operating system being used.

To find out and remove the error cause, consult the documentation on the operating system.

Check whether a typing error or the specification of a directory instead of a file could have caused the error.