diff --git a/src/main/java/sirius/biz/storage/layer2/jdbc/SQLBlobStorageSpace.java b/src/main/java/sirius/biz/storage/layer2/jdbc/SQLBlobStorageSpace.java
index 1429583b6..746507c8e 100644
--- a/src/main/java/sirius/biz/storage/layer2/jdbc/SQLBlobStorageSpace.java
+++ b/src/main/java/sirius/biz/storage/layer2/jdbc/SQLBlobStorageSpace.java
@@ -31,6 +31,7 @@
 import sirius.kernel.commons.Files;
 import sirius.kernel.commons.Strings;
 import sirius.kernel.commons.Tuple;
+import sirius.kernel.commons.Value;
 import sirius.kernel.di.std.Part;
 import sirius.kernel.health.Exceptions;
 import sirius.kernel.nls.NLS;
@@ -661,7 +662,7 @@ protected void listChildDirectories(SQLDirectory parent,
            .eq(SQLDirectory.COMMITTED, true)
            .eq(SQLDirectory.DELETED, false)
            .where(OMA.FILTERS.like(SQLDirectory.NORMALIZED_DIRECTORY_NAME)
-                             .startsWith(prefixFilter)
+                             .startsWith(Value.of(prefixFilter).toLowerCase())
                              .ignoreEmpty()
                              .build())
            .limit(maxResults)
diff --git a/src/main/java/sirius/biz/storage/layer2/jdbc/SQLDirectory.java b/src/main/java/sirius/biz/storage/layer2/jdbc/SQLDirectory.java
index dcd4b712f..fd82f00ce 100644
--- a/src/main/java/sirius/biz/storage/layer2/jdbc/SQLDirectory.java
+++ b/src/main/java/sirius/biz/storage/layer2/jdbc/SQLDirectory.java
@@ -20,6 +20,7 @@
 import sirius.db.mixing.annotations.BeforeSave;
 import sirius.db.mixing.annotations.Index;
 import sirius.db.mixing.annotations.Length;
+import sirius.db.mixing.annotations.LowerCase;
 import sirius.db.mixing.annotations.NullAllowed;
 import sirius.db.mixing.annotations.Transient;
 import sirius.db.mixing.types.BaseEntityRef;
@@ -76,6 +77,7 @@ public class SQLDirectory extends SQLEntity implements Directory, OptimisticCrea
      */
     public static final Mapping NORMALIZED_DIRECTORY_NAME = Mapping.named("normalizedDirectoryName");
     @Length(255)
+    @LowerCase
     @NullAllowed
     private String normalizedDirectoryName;
 
@@ -131,7 +133,7 @@ protected void beforeSave() {
         if (Strings.isFilled(directoryName)) {
             this.directoryName = storageUtils.sanitizePath(directoryName);
             if (Strings.isFilled(directoryName)) {
-                this.normalizedDirectoryName = directoryName.toLowerCase();
+                this.normalizedDirectoryName = directoryName;
             } else {
                 this.directoryName = null;
                 this.normalizedDirectoryName = null;
diff --git a/src/main/java/sirius/biz/storage/layer2/mongo/MongoDirectory.java b/src/main/java/sirius/biz/storage/layer2/mongo/MongoDirectory.java
index e3067816a..af2d7568f 100644
--- a/src/main/java/sirius/biz/storage/layer2/mongo/MongoDirectory.java
+++ b/src/main/java/sirius/biz/storage/layer2/mongo/MongoDirectory.java
@@ -17,6 +17,7 @@
 import sirius.db.mixing.Mapping;
 import sirius.db.mixing.annotations.BeforeSave;
 import sirius.db.mixing.annotations.Index;
+import sirius.db.mixing.annotations.LowerCase;
 import sirius.db.mixing.annotations.NullAllowed;
 import sirius.db.mixing.annotations.Transient;
 import sirius.db.mixing.types.BaseEntityRef;
@@ -78,6 +79,7 @@ public class MongoDirectory extends MongoEntity implements Directory, Optimistic
      */
     public static final Mapping NORMALIZED_DIRECTORY_NAME = Mapping.named("normalizedDirectoryName");
     @NullAllowed
+    @LowerCase
     private String normalizedDirectoryName;
 
     /**
@@ -131,7 +133,7 @@ protected void beforeSave() {
         if (Strings.isFilled(directoryName)) {
             this.directoryName = storageUtils.sanitizePath(directoryName);
             if (Strings.isFilled(directoryName)) {
-                this.normalizedDirectoryName = directoryName.toLowerCase();
+                this.normalizedDirectoryName = directoryName;
             } else {
                 this.directoryName = null;
                 this.normalizedDirectoryName = null;