diff --git a/Channel.cpp b/Channel.cpp
index 15e74a2..05ada7c 100644
--- a/Channel.cpp
+++ b/Channel.cpp
@@ -27,7 +27,6 @@ void Channel::handle(const shared_ptr<U2FMessage> uMsg)
 	else if (this->lockedState != ChannelLockedState::Unlocked)
 		throw runtime_error{ "Channel in incorrect (locked) state to handle request" };
 
-	clog << "Handling uMsg with CMD: " << static_cast<uint32_t>(uMsg->cmd) << endl;
 	return U2F_CMD::get(uMsg)->respond(this->cid);
 }
 
diff --git a/Controller.cpp b/Controller.cpp
index a008d96..1b15ff2 100644
--- a/Controller.cpp
+++ b/Controller.cpp
@@ -18,8 +18,6 @@ void Controller::handleTransaction()
 
 	auto opChannel = msg->cid;
 
-	clog << "Got msg with cmd of: " << static_cast<uint16_t>(msg->cmd) << endl;
-
 	if (msg->cmd == U2FHID_INIT)
 	{
 		opChannel = nextChannel();
diff --git a/Packet.cpp b/Packet.cpp
index 60e335a..a0e34e9 100644
--- a/Packet.cpp
+++ b/Packet.cpp
@@ -90,7 +90,6 @@ shared_ptr<InitPacket> InitPacket::getPacket(const uint32_t rCID, const uint8_t
 			"\t\t</table>"
 			"\t\t<br />");
 
-	clog << "Fully read init packet" << endl;
 	bytesRead = 0;
 	return p;
 }
@@ -143,7 +142,6 @@ shared_ptr<ContPacket> ContPacket::getPacket(const uint32_t rCID, const uint8_t
 			"\t\t</table>\n"
 			"\t\t<br />");
 
-	//clog << "Fully read cont packet" << endl;
 	readBytes = 0;
 	return p;
 }
@@ -183,7 +181,6 @@ shared_ptr<Packet> Packet::getPacket()
 			if (b & TYPE_MASK)
 			{
 				//Init packet
-				//clog << "Getting init packet" << endl;
 				packet = InitPacket::getPacket(cid, b);
 
 				if (packet)
@@ -194,7 +191,6 @@ shared_ptr<Packet> Packet::getPacket()
 			else
 			{
 				//Cont packet
-				//clog << "Getting cont packet" << endl;
 				packet = ContPacket::getPacket(cid, b);
 
 				if (packet)
diff --git a/Storage.cpp b/Storage.cpp
index 4a66b29..8d39d45 100644
--- a/Storage.cpp
+++ b/Storage.cpp
@@ -50,13 +50,6 @@ void Storage::init(const string &dirPrefix)
 		Storage::PubKey   pubKey{};
 		b64decode(pubStr, pubKey);
 
-		clog << "Loaded key with pubkey: " << hex;
-
-		for (auto b : pubKey)
-			clog << static_cast<uint32_t>(b) << ' ';
-
-		clog << dec << endl;
-
 		Storage::appParams[keyH] = appParam;
 		Storage::privKeys[keyH]  = privKey;
 		Storage::pubKeys[keyH]   = pubKey;
diff --git a/U2FMessage.cpp b/U2FMessage.cpp
index 1ab8e45..02c063e 100644
--- a/U2FMessage.cpp
+++ b/U2FMessage.cpp
@@ -85,8 +85,6 @@ shared_ptr<U2FMessage> U2FMessage::readNonBlock()
 	message->data.assign(dataBytes.begin(), dataBytes.end());
 	currSeq = -1u;
 
-	std::clog << "Read all of message" << std::endl;
-
 	return message;
 }
 
@@ -128,8 +126,6 @@ void U2FMessage::write()
 		bytesWritten += newByteCount;
 	}
 
-	//auto stream = *getHostStream();
-
 	if (cmd == U2FHID_MSG)
 	{
 		auto dAS = getDevAPDUStream().get();
diff --git a/U2F_Authenticate_APDU.cpp b/U2F_Authenticate_APDU.cpp
index 5a6b409..ba1f9d6 100644
--- a/U2F_Authenticate_APDU.cpp
+++ b/U2F_Authenticate_APDU.cpp
@@ -23,8 +23,6 @@ U2F_Authenticate_APDU::U2F_Authenticate_APDU(const U2F_Msg_CMD &msg, const vecto
 	uint8_t keyHLen = data[64];
 
 	copy(data.begin() + 65, data.begin() + 65 + keyHLen, back_inserter(keyH));
-
-	clog << "Got U2F_Auth request" << endl;
 }
 
 void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
@@ -39,7 +37,7 @@ void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
 	if (keyH.size() != sizeof(Storage::KeyHandle))
 	{
 		//Respond with error code - key handle is of wrong size
-		clog << "Invalid key handle length" << endl;
+		cerr << "Invalid key handle length" << endl;
 		statusCode = APDU_STATUS::SW_WRONG_DATA;
 		response.insert(response.end(), FIELD_BE(statusCode));
 		msg.write();
@@ -51,7 +49,7 @@ void U2F_Authenticate_APDU::respond(const uint32_t channelID) const
 	if (Storage::appParams.find(keyHB) == Storage::appParams.end())
 	{
 		//Respond with error code - key handle doesn't exist in storage
-		clog << "Invalid key handle" << endl;
+		cerr << "Invalid key handle" << endl;
 		statusCode = APDU_STATUS::SW_WRONG_DATA;
 		response.insert(response.end(), FIELD_BE(statusCode));
 		msg.write();
diff --git a/U2F_Msg_CMD.cpp b/U2F_Msg_CMD.cpp
index 7aedb64..68bc375 100644
--- a/U2F_Msg_CMD.cpp
+++ b/U2F_Msg_CMD.cpp
@@ -17,9 +17,7 @@ uint32_t U2F_Msg_CMD::getLe(const uint32_t byteCount, vector<uint8_t> bytes)
 	if (byteCount != 0)
 	{
 		//Le must be length of data in bytes
-		clog << "Le must be length of data in bytes" << endl;
-		clog << "Le has a size of " << byteCount << " bytes" << endl;
-
+		
 		switch (byteCount)
 		{
 			case 1:
@@ -59,14 +57,10 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 	cmd.p1  = dat[2];
 	cmd.p2  = dat[3];
 
-	clog << "Loaded U2F_Msg_CMD parameters" << endl;
-
 	vector<uint8_t> data{ dat.begin() + 4, dat.end() };
 	const uint32_t cBCount = data.size();
 	auto startPtr = data.begin(), endPtr = data.end();
 
-	clog << "Loaded iters" << endl;
-
 	if (usesData.at(cmd.ins) || data.size() > 3)
 	{
 		if (cBCount == 0)
@@ -85,7 +79,6 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 
 		endPtr = startPtr + cmd.lc;
 
-		clog << "Getting Le" << endl;
 		cmd.le = getLe(data.end() - endPtr, vector<uint8_t>(endPtr, data.end()));
 	}
 	else
@@ -93,14 +86,11 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 		cmd.lc = 0;
 		endPtr = startPtr;
 
-		clog << "Getting Le" << endl;
 		cmd.le = getLe(cBCount, data);
 	}
 
 	const auto dBytes = vector<uint8_t>(startPtr, endPtr);
 
-	clog << "Determined message format" << endl;
-
 	auto hAS = getHostAPDUStream().get();
 
 	fprintf(hAS, "<table>\n"
@@ -134,8 +124,6 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 			"\t\t</table>\n"
 			"\t\t<br />", cmd.le);
 
-	clog << "Constructing message specialisation" << endl;
-
 	switch (cmd.ins)
 	{
 		case APDU::U2F_REG:
@@ -149,6 +137,15 @@ shared_ptr<U2F_Msg_CMD> U2F_Msg_CMD::generate(const shared_ptr<U2FMessage> uMsg)
 	}
 }
 
+void U2F_Msg_CMD::error(const uint32_t channelID, const uint16_t errCode)
+{
+	U2FMessage msg{};
+	msg.cid = channelID;
+	msg.cmd = U2FHID_MSG;
+	msg.data.insert(msg.data.end(), FIELD_BE(errCode));
+	msg.write();
+}
+
 const map<uint8_t, bool> U2F_Msg_CMD::usesData = {
 	{ U2F_REG,  true  },
 	{ U2F_AUTH, true  },
@@ -157,10 +154,5 @@ const map<uint8_t, bool> U2F_Msg_CMD::usesData = {
 
 void U2F_Msg_CMD::respond(const uint32_t channelID) const
 {
-	U2FMessage msg{};
-	msg.cid = channelID;
-	msg.cmd = U2FHID_MSG;
-	auto errorCode = APDU_STATUS::SW_INS_NOT_SUPPORTED;
-	msg.data.insert(msg.data.end(), FIELD_BE(errorCode));
-	msg.write();
+	U2F_Msg_CMD::error(channelID, static_cast<uint16_t>(APDU_STATUS::SW_INS_NOT_SUPPORTED));
 }
diff --git a/U2F_Msg_CMD.hpp b/U2F_Msg_CMD.hpp
index aa5ffdc..7403d1e 100644
--- a/U2F_Msg_CMD.hpp
+++ b/U2F_Msg_CMD.hpp
@@ -22,6 +22,7 @@ struct U2F_Msg_CMD : U2F_CMD
 
 	public:
 		static std::shared_ptr<U2F_Msg_CMD> generate(const std::shared_ptr<U2FMessage> uMsg);
+		static void error(const uint32_t channelID, const uint16_t errCode);
 		void respond(const uint32_t channelID) const;
 };
 
diff --git a/U2F_Register_APDU.cpp b/U2F_Register_APDU.cpp
index a67ee81..63d7308 100644
--- a/U2F_Register_APDU.cpp
+++ b/U2F_Register_APDU.cpp
@@ -19,8 +19,8 @@ U2F_Register_APDU::U2F_Register_APDU(const U2F_Msg_CMD &msg, const vector<uint8_
 		throw runtime_error{ "Incorrect registration size" };
 	else if (p1 != 0x00 || p2 != 0x00)
 	{
-		cerr << "p1: " << static_cast<uint32_t>(p1) << ", p2: " << static_cast<uint32_t>(p2) << endl;
-		//throw runtime_error{ "Invalid APDU parameters" };
+		cerr << "Ins: " << static_cast<uint32_t>(ins) << ", p1: " << static_cast<uint32_t>(p1) << ", p2: " << static_cast<uint32_t>(p2) << endl;
+		cerr << "Invalid APDU parameters detected" << endl;
 	}
 
 	copy(data.data() + 0,  data.data() + 32, challengeP.begin());
@@ -31,7 +31,6 @@ U2F_Register_APDU::U2F_Register_APDU(const U2F_Msg_CMD &msg, const vector<uint8_
 	Storage::PubKey pubKey{};
 	
 	//Unsure if necessary
-	//From github.com/pratikd650/Teensy_U2F/blob/master/Teensy_U2F.cpp
 	pubKey[0] = 0x04;
 
 	uECC_make_key(pubKey.data() + 1, privKey.data(), uECC_secp256r1());
@@ -41,13 +40,6 @@ U2F_Register_APDU::U2F_Register_APDU(const U2F_Msg_CMD &msg, const vector<uint8_
 	Storage::privKeys[this->keyH]  = privKey;
 	Storage::pubKeys[this->keyH]   = pubKey;
 	Storage::keyCounts[this->keyH] = 0;
-
-	clog << "Produced pub key: " << hex;
-
-	for (auto b : pubKey)
-		clog << static_cast<uint32_t>(b) << ' ';
-
-	clog << endl << dec << "Got U2F_Reg request" << endl;
 }
 
 void U2F_Register_APDU::respond(const uint32_t channelID) const
@@ -59,7 +51,6 @@ void U2F_Register_APDU::respond(const uint32_t channelID) const
 	auto& response = m.data;
 	const auto appParam = Storage::appParams[this->keyH];
 	const auto pubKey   = Storage::pubKeys[this->keyH];
-	const auto privKey  = Storage::privKeys[this->keyH];
 
 	response.push_back(0x05);
 	copy(pubKey.begin(), pubKey.end(), back_inserter(response));
@@ -94,17 +85,13 @@ void U2F_Register_APDU::respond(const uint32_t channelID) const
 	}
 
 	Signature signature;
-	std::clog << "Will sign digest with priv key" << std::endl;
 	uECC_sign(attestPrivKey, digest.data(), digest.size(), signature.data(), uECC_secp256r1());
 
 	//Append signature as DER
-	std::clog << "Will append sig as DER" << std::endl;
 	appendSignatureAsDER(response, signature);
 
 	response.push_back(static_cast<uint16_t>(APDU_STATUS::SW_NO_ERROR) >> 8);
 	response.push_back(static_cast<uint16_t>(APDU_STATUS::SW_NO_ERROR) & 0xff);
 
-	std::clog << "Writing out " << response.size() << " bytes in response" << std::endl;
-
 	m.write();
 }
diff --git a/U2F_Version_APDU.cpp b/U2F_Version_APDU.cpp
index 3d1df44..b5af8dc 100644
--- a/U2F_Version_APDU.cpp
+++ b/U2F_Version_APDU.cpp
@@ -9,8 +9,6 @@ using namespace std;
 
 U2F_Version_APDU::U2F_Version_APDU(const U2F_Msg_CMD &msg)
 {
-	clog << "Got U2F_Ver APDU request" << endl;
-
 	//Don't actually respond yet
 }