diff --git a/CMakeLists.txt b/CMakeLists.txt
index 877e7b6..6b2ac88 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -48,6 +48,10 @@ add_executable(App ./src/main.cpp
                    ./src/DAO/MemoryAuthDAO.cpp
                    ./src/DAO/MemoryAuthDAO.h
                    ./src/endpoints_handlers/AuthLogoutExecutor.h
+                   ./src/exceptions/exception400_bad_request.cpp
+                   ./src/exceptions/exception400_bad_request.h
+                   ./src/exceptions/exception409_conflict.cpp
+                   ./src/exceptions/exception409_conflict.h
 )
 
 target_link_libraries(App PRIVATE Boost::boost Boost::json Threads::Threads mysql::concpp)
diff --git a/src/exceptions/exception400_bad_request.cpp b/src/exceptions/exception400_bad_request.cpp
new file mode 100644
index 0000000..5df2403
--- /dev/null
+++ b/src/exceptions/exception400_bad_request.cpp
@@ -0,0 +1,18 @@
+#include "exception400_bad_request.h"
+
+#include <boost/beast/core/error.hpp>
+
+using namespace std;
+using namespace std::literals;
+
+namespace uad
+{
+exception400_bad_request::exception400_bad_request(const string& info): message_(info)
+{
+}
+
+char const* exception400_bad_request::what() const
+{
+  return message_.c_str();
+}
+}
diff --git a/src/exceptions/exception400_bad_request.h b/src/exceptions/exception400_bad_request.h
new file mode 100644
index 0000000..c52ecac
--- /dev/null
+++ b/src/exceptions/exception400_bad_request.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <exception>
+#include <string>
+
+namespace uad
+{
+struct exception400_bad_request : std::exception
+{
+private:
+  std::string message_;
+public:
+  exception400_bad_request(const std::string& info);
+  char const* what() const override;
+};
+}
diff --git a/src/exceptions/exception409_conflict.cpp b/src/exceptions/exception409_conflict.cpp
new file mode 100644
index 0000000..4f387f9
--- /dev/null
+++ b/src/exceptions/exception409_conflict.cpp
@@ -0,0 +1,18 @@
+#include "exception409_conflict.h"
+
+#include <boost/beast/core/error.hpp>
+
+using namespace std;
+using namespace std::literals;
+
+namespace uad
+{
+exception409_conflict::exception409_conflict(const string& info): message_(info)
+{
+}
+
+char const* exception409_conflict::what() const
+{
+  return message_.c_str();
+}
+}
diff --git a/src/exceptions/exception409_conflict.h b/src/exceptions/exception409_conflict.h
new file mode 100644
index 0000000..b930ef3
--- /dev/null
+++ b/src/exceptions/exception409_conflict.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <exception>
+#include <string>
+
+namespace uad
+{
+struct exception409_conflict : std::exception
+{
+private:
+  std::string message_;
+public:
+  exception409_conflict(const std::string& info);
+  char const* what() const override;
+};
+}