diff --git a/src/application/libraries/Unit_tests/drivers/Unit_tests_appointments_model.php b/src/application/libraries/Unit_tests/drivers/Unit_tests_appointments_model.php
index adc14f7e..b9c00a11 100644
--- a/src/application/libraries/Unit_tests/drivers/Unit_tests_appointments_model.php
+++ b/src/application/libraries/Unit_tests/drivers/Unit_tests_appointments_model.php
@@ -66,7 +66,7 @@ class Unit_tests_appointments_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
diff --git a/src/application/libraries/Unit_tests/drivers/Unit_tests_customers_model.php b/src/application/libraries/Unit_tests/drivers/Unit_tests_customers_model.php
index dd3ab55a..0cf716dc 100644
--- a/src/application/libraries/Unit_tests/drivers/Unit_tests_customers_model.php
+++ b/src/application/libraries/Unit_tests/drivers/Unit_tests_customers_model.php
@@ -96,7 +96,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -151,7 +151,7 @@ class Unit_tests_customers_model extends CI_Driver {
         // Prepare customer's data (last name field is missing).
         $customer = array(
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -176,7 +176,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -243,7 +243,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -293,7 +293,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -310,7 +310,7 @@ class Unit_tests_customers_model extends CI_Driver {
         // Prepare customer's data (no last_name value provided).
         $customer = array(
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -361,7 +361,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -439,7 +439,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -473,7 +473,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -520,7 +520,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -560,7 +560,7 @@ class Unit_tests_customers_model extends CI_Driver {
         $customer = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
diff --git a/src/application/libraries/Unit_tests/drivers/Unit_tests_providers_model.php b/src/application/libraries/Unit_tests/drivers/Unit_tests_providers_model.php
index cf9d6006..d21c58b2 100644
--- a/src/application/libraries/Unit_tests/drivers/Unit_tests_providers_model.php
+++ b/src/application/libraries/Unit_tests/drivers/Unit_tests_providers_model.php
@@ -629,7 +629,7 @@ class Unit_tests_providers_model extends CI_Driver {
         $provider = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -706,7 +706,7 @@ class Unit_tests_providers_model extends CI_Driver {
         $provider = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -746,7 +746,7 @@ class Unit_tests_providers_model extends CI_Driver {
         $provider = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',
@@ -808,7 +808,7 @@ class Unit_tests_providers_model extends CI_Driver {
         $provider = array(
             'last_name' => 'Doe',
             'first_name' => 'John',
-            'email' => 'alextselegidis@gmail.com',
+            'email' => 'john@doe.com',
             'phone_number' => '0123456789',
             'address' => 'Abbey Road 18',
             'city' => 'London',