diff --git a/admin/sync/full.go b/admin/sync/full.go
index 0eb6b528..f92b5961 100644
--- a/admin/sync/full.go
+++ b/admin/sync/full.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"path"
 	"time"
 	"sync"
 
@@ -31,7 +32,19 @@ func SyncDeep(i Importer) map[string][]string {
 				for _, exercice := range exercices {
 					errs[theme.Name] = append(errs[theme.Name], SyncExerciceFiles(i, exercice)...)
 					errs[theme.Name] = append(errs[theme.Name], SyncExerciceHints(i, exercice)...)
-					errs[theme.Name] = append(errs[theme.Name], SyncExerciceKeys(i, exercice)...)
+
+					hasFlags := false
+					if i.exists(path.Join(exercice.Path, "flags.txt")) {
+						errs[theme.Name] = append(errs[theme.Name], SyncExerciceKeys(i, exercice)...)
+						hasFlags = true
+					}
+					if i.exists(path.Join(exercice.Path, "flags-mcq.txt")) || i.exists(path.Join(exercice.Path, "flags-ucq.txt")) {
+						errs[theme.Name] = append(errs[theme.Name], SyncExerciceMCQ(i, exercice)...)
+						hasFlags = true
+					}
+					if !hasFlags {
+						errs[theme.Name] = append(errs[theme.Name], fmt.Sprintf("%q: has no flags!", path.Base(exercice.Path)))
+					}
 				}
 			}
 		}