diff --git a/core/userrights.class.inc.php b/core/userrights.class.inc.php
index 9f3f10af2..bcd3c6163 100644
--- a/core/userrights.class.inc.php
+++ b/core/userrights.class.inc.php
@@ -289,45 +289,52 @@ abstract class User extends cmdbAbstractObject
 			$oSet = $this->Get('profile_list');
 			if ($oSet->Count() == 0)
 			{
-				$this->m_aCheckIssues[] = Dict::Format('Class:User/Error:AtLeastOneProfileIsNeeded');
+				$this->m_aCheckIssues[] = Dict::S('Class:User/Error:AtLeastOneProfileIsNeeded');
 			}
 		}
 		// Only administrators can manage administrators
 		if (UserRights::IsAdministrator($this) && !UserRights::IsAdministrator())
 		{
-			$this->m_aCheckIssues[] = Dict::Format('UI:Login:Error:AccessRestricted');
+			$this->m_aCheckIssues[] = Dict::S('UI:Login:Error:AccessRestricted');
 		}
 
 		if (!UserRights::IsAdministrator())
 		{
-			$oUser = UserRights::GetUserObject();
-			$oAddon = UserRights::GetModuleInstance();
-			if (!is_null($oUser) && method_exists($oAddon, 'GetUserOrgs'))
+			if (empty($this->GetOriginal('org_id')) || empty($this->Get('org_id')))
 			{
-				$aOrgs = $oAddon->GetUserOrgs($oUser, '');
-				if (count($aOrgs) > 0)
+				$this->m_aCheckIssues[] = Dict::S('Class:User/Error:PersonIsMandatory');
+			}
+			else
+			{
+				$oUser = UserRights::GetUserObject();
+				$oAddon = UserRights::GetModuleInstance();
+				if (!is_null($oUser) && method_exists($oAddon, 'GetUserOrgs'))
 				{
-					// Check that the modified User belongs to one of our organization
-					if (!in_array($this->GetOriginal('org_id'), $aOrgs) && !in_array($this->Get('org_id'), $aOrgs))
+					$aOrgs = $oAddon->GetUserOrgs($oUser, '');
+					if (count($aOrgs) > 0)
 					{
-						$this->m_aCheckIssues[] = Dict::Format('Class:User/Error:UserOrganizationNotAllowed');
-					}
-					// Check users with restricted organizations when allowed organizations have changed
-					if ($this->IsNew() || array_key_exists('allowed_org_list', $aChanges))
-					{
-						$oSet = $this->get('allowed_org_list');
-						if ($oSet->Count() == 0)
+						// Check that the modified User belongs to one of our organization
+						if (!in_array($this->GetOriginal('org_id'), $aOrgs) && !in_array($this->Get('org_id'), $aOrgs))
 						{
-							$this->m_aCheckIssues[] = Dict::Format('Class:User/Error:AtLeastOneOrganizationIsNeeded');
+							$this->m_aCheckIssues[] = Dict::S('Class:User/Error:UserOrganizationNotAllowed');
 						}
-						else
+						// Check users with restricted organizations when allowed organizations have changed
+						if ($this->IsNew() || array_key_exists('allowed_org_list', $aChanges))
 						{
-							$aModifiedLinks = $oSet->ListModifiedLinks();
-							foreach($aModifiedLinks as $oLink)
+							$oSet = $this->get('allowed_org_list');
+							if ($oSet->Count() == 0)
 							{
-								if (!in_array($oLink->Get('allowed_org_id'), $aOrgs))
+								$this->m_aCheckIssues[] = Dict::S('Class:User/Error:AtLeastOneOrganizationIsNeeded');
+							}
+							else
+							{
+								$aModifiedLinks = $oSet->ListModifiedLinks();
+								foreach ($aModifiedLinks as $oLink)
 								{
-									$this->m_aCheckIssues[] = Dict::Format('Class:User/Error:OrganizationNotAllowed');
+									if (!in_array($oLink->Get('allowed_org_id'), $aOrgs))
+									{
+										$this->m_aCheckIssues[] = Dict::S('Class:User/Error:OrganizationNotAllowed');
+									}
 								}
 							}
 						}
diff --git a/dictionaries/en.dictionary.itop.ui.php b/dictionaries/en.dictionary.itop.ui.php
index a30716005..f7ed54807 100644
--- a/dictionaries/en.dictionary.itop.ui.php
+++ b/dictionaries/en.dictionary.itop.ui.php
@@ -141,6 +141,7 @@ Dict::Add('EN US', 'English', 'English', array(
 	'Class:User/Error:AtLeastOneOrganizationIsNeeded' => 'At least one organization must be assigned to this user.',
 	'Class:User/Error:OrganizationNotAllowed' => 'Organization not allowed.',
 	'Class:User/Error:UserOrganizationNotAllowed' => 'The user account does not belong to your allowed organizations.',
+	'Class:User/Error:PersonIsMandatory' => 'The Contact is mandatory.',
 	'Class:UserInternal' => 'User Internal',
 	'Class:UserInternal+' => 'User defined within iTop',
 ));
diff --git a/dictionaries/fr.dictionary.itop.ui.php b/dictionaries/fr.dictionary.itop.ui.php
index 90536c108..e11daa171 100644
--- a/dictionaries/fr.dictionary.itop.ui.php
+++ b/dictionaries/fr.dictionary.itop.ui.php
@@ -121,6 +121,7 @@ Dict::Add('FR FR', 'French', 'Français', array(
 	'Class:User/Error:AtLeastOneOrganizationIsNeeded' => 'L\'utilisateur doit avoir au moins une organisation.',
 	'Class:User/Error:OrganizationNotAllowed' => 'Organisation non autorisée.',
 	'Class:User/Error:UserOrganizationNotAllowed' => 'L\'utilisateur n\'appartient pas à vos organisations.',
+	'Class:User/Error:PersonIsMandatory' => 'Le Contact est obligatoire.',
 	'Class:UserInternal' => 'Utilisateur interne',
 	'Class:UserInternal+' => 'Utilisateur défini dans iTop',
 ));
diff --git a/webservices/rest.php b/webservices/rest.php
index aab2958c6..0b5843efd 100644
--- a/webservices/rest.php
+++ b/webservices/rest.php
@@ -165,7 +165,7 @@ try
 	
 	if ($sJsonString == null)
 	{
-		throw new Exception("Missing parameter 'json_data", RestResult::MISSING_JSON);
+		throw new Exception("Missing parameter 'json_data'", RestResult::MISSING_JSON);
 	}
 	$aJsonData = @json_decode($sJsonString);
 	if ($aJsonData == null)