Index: lams_common/conf/language/lams/ApplicationResources.properties
===================================================================
diff -u -red98b3790d94f07748756535ad1bebd3d97d01be -r423858087ec4d185fb33c3f569fc7ede1d43001a
--- lams_common/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision ed98b3790d94f07748756535ad1bebd3d97d01be)
+++ lams_common/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision 423858087ec4d185fb33c3f569fc7ede1d43001a)
@@ -56,7 +56,7 @@
 email.notifications.lesson = lesson
 email.notifications.tool = tool
 email.notifications.activity = activity
-error.requires.existing.grouping = Activity {0} requires existing grouping but no group for user {1} exists yet.
+error.requires.existing.grouping = In this activity you work in groups. Please visit the grouping activity first.
 validation.error.GroupingNotUsed = Grouping is not used in any of activities
 audit.change.mark = User {3} ({4})  Changed mark for user {0}. Old mark: {1}, new mark: {2}
 audit.started.editing.activity = Teacher {0} has started editing activity {1} in monitor