diff --git a/app/controllers/usergroups_controller.rb b/app/controllers/usergroups_controller.rb
index b633f906739..4079b29ffe8 100644
--- a/app/controllers/usergroups_controller.rb
+++ b/app/controllers/usergroups_controller.rb
@@ -37,7 +37,7 @@ def update
       process_error
     end
   rescue Foreman::CyclicGraphException => e
-    @usergroup.errors[:usergroups] << e.record.errors[:base].join(' ')
+    @usergroup.errors.add(:usergroups, e.record.errors[:base].join(' '))
     process_error
   rescue => e
     external_usergroups_error(@usergroup, e)
diff --git a/app/models/compute_resources/foreman/model/ec2.rb b/app/models/compute_resources/foreman/model/ec2.rb
index 930b3316b60..d801542190a 100644
--- a/app/models/compute_resources/foreman/model/ec2.rb
+++ b/app/models/compute_resources/foreman/model/ec2.rb
@@ -122,9 +122,9 @@ def test_connection(options = {})
       super
       errors[:user].empty? && errors[:password].empty? && regions
     rescue Fog::AWS::Compute::Error => e
-      errors[:base] << e.message
+      errors.add(:base, e.message)
     rescue Excon::Error::Socket => e
-      errors[:base] << e.message
+      errors.add(:base, e.message)
     end
 
     def console(uuid)
diff --git a/app/models/compute_resources/foreman/model/libvirt.rb b/app/models/compute_resources/foreman/model/libvirt.rb
index 23d367de42b..f5360fbd61f 100644
--- a/app/models/compute_resources/foreman/model/libvirt.rb
+++ b/app/models/compute_resources/foreman/model/libvirt.rb
@@ -78,7 +78,7 @@ def test_connection(options = {})
       errors[:url].empty? && hypervisor
     rescue => e
       disconnect rescue nil
-      errors[:base] << e.message
+      errors.add(:base, e.message)
     end
 
     def new_nic(attr = {})
diff --git a/app/models/compute_resources/foreman/model/openstack.rb b/app/models/compute_resources/foreman/model/openstack.rb
index 3a414cfa4a3..44154ace9f8 100644
--- a/app/models/compute_resources/foreman/model/openstack.rb
+++ b/app/models/compute_resources/foreman/model/openstack.rb
@@ -91,7 +91,7 @@ def test_connection(options = {})
       super
       errors[:user].empty? && errors[:password] && tenants
     rescue => e
-      errors[:base] << e.message
+      errors.add(:base, e.message)
     end
 
     def available_images
diff --git a/app/models/compute_resources/foreman/model/vmware.rb b/app/models/compute_resources/foreman/model/vmware.rb
index 76c7ea8e9ee..1a5284f454e 100644
--- a/app/models/compute_resources/foreman/model/vmware.rb
+++ b/app/models/compute_resources/foreman/model/vmware.rb
@@ -470,7 +470,7 @@ def test_connection(options = {})
         errors.delete(:datacenter)
       end
     rescue => e
-      errors[:base] << e.message
+      errors.add(:base, e.message)
     end
 
     def parse_args(args)