case E_INVALID_PROXY:
IsErrFatal(int aErr){    int bFatal = TRUE;    /* non-fatal errors */    switch (aErr)    {        case E_XPI_FAIL:        case E_INSTALL:        case E_MKDIR_FAIL:        case E_OLD_INST:        case E_DIR_NOT_EMPTY:            bFatal = FALSE;        default:            break;     }    return bFatal;}