Abra o seu items.cpp e localize esta parte:

if(Items::dwMajorVersion == 0xFFFFFFFF)
	std::clog << "[Warning - Items::loadFromOtb] items.otb using generic client version." << std::endl;
else if(Items::dwMajorVersion < 3) {
	std::clog << "[Error - Items::loadFromOtb] Old version detected, a newer version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}
else if(Items::dwMajorVersion > 3) {
	std::clog << "[Error - Items::loadFromOtb] New version detected, an older version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}
else if(!g_config.getBool(ConfigManager::SKIP_ITEMS_VERSION) && Items::dwMinorVersion != CLIENT_VERSION_920) {
	std::clog << "[Error - Items::loadFromOtb] Another (client) version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}

Basta comentá-la, ficando assim:

/*if(Items::dwMajorVersion == 0xFFFFFFFF)
	std::clog << "[Warning - Items::loadFromOtb] items.otb using generic client version." << std::endl;
else if(Items::dwMajorVersion < 3) {
	std::clog << "[Error - Items::loadFromOtb] Old version detected, a newer version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}
else if(Items::dwMajorVersion > 3) {
	std::clog << "[Error - Items::loadFromOtb] New version detected, an older version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}
else if(!g_config.getBool(ConfigManager::SKIP_ITEMS_VERSION) && Items::dwMinorVersion != CLIENT_VERSION_920) {
	std::clog << "[Error - Items::loadFromOtb] Another (client) version of items.otb is required." << std::endl;
	return ERROR_INVALID_FORMAT;
}*/

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