diff --git a/src/Squidex.Infrastructure.MongoDb/MongoDb/BsonJsonWriter.cs b/src/Squidex.Infrastructure.MongoDb/MongoDb/BsonJsonWriter.cs
index 52b3ac5d3..5b485c624 100644
--- a/src/Squidex.Infrastructure.MongoDb/MongoDb/BsonJsonWriter.cs
+++ b/src/Squidex.Infrastructure.MongoDb/MongoDb/BsonJsonWriter.cs
@@ -135,12 +135,12 @@ namespace Squidex.Infrastructure.MongoDb
 
         public override void WriteValue(DateTime value)
         {
-            bsonWriter.WriteString(value.ToString(CultureInfo.InvariantCulture));
+            bsonWriter.WriteString(value.ToString("yyyy-MM-ddTHH:mm:ssZ", CultureInfo.InvariantCulture));
         }
 
         public override void WriteValue(DateTimeOffset value)
         {
-            bsonWriter.WriteString(value.ToString(CultureInfo.InvariantCulture));
+            bsonWriter.WriteString(value.ToString("yyyy-MM-ddTHH:mm:ssZ", CultureInfo.InvariantCulture));
         }
 
         public override void WriteValue(byte[] value)
diff --git a/src/Squidex.Infrastructure/Log/JsonLogWriter.cs b/src/Squidex.Infrastructure/Log/JsonLogWriter.cs
index 07851ac5b..987785280 100644
--- a/src/Squidex.Infrastructure/Log/JsonLogWriter.cs
+++ b/src/Squidex.Infrastructure/Log/JsonLogWriter.cs
@@ -56,14 +56,14 @@ namespace Squidex.Infrastructure.Log
 
         IArrayWriter IArrayWriter.WriteValue(DateTime value)
         {
-            jsonWriter.WriteValue(value.ToString("o", CultureInfo.InvariantCulture));
+            jsonWriter.WriteValue(value.ToString("yyyy-MM-ddTHH:mm:ssZ", CultureInfo.InvariantCulture));
 
             return this;
         }
 
         IArrayWriter IArrayWriter.WriteValue(DateTimeOffset value)
         {
-            jsonWriter.WriteValue(value.ToString("o", CultureInfo.InvariantCulture));
+            jsonWriter.WriteValue(value.ToString("yyyy-MM-ddTHH:mm:ss.fffZ", CultureInfo.InvariantCulture));
 
             return this;
         }
diff --git a/tools/Migrate_01/MigrationPath.cs b/tools/Migrate_01/MigrationPath.cs
index 030b87094..5be1fcdb7 100644
--- a/tools/Migrate_01/MigrationPath.cs
+++ b/tools/Migrate_01/MigrationPath.cs
@@ -15,7 +15,7 @@ namespace Migrate_01
 {
     public sealed class MigrationPath : IMigrationPath
     {
-        private const int CurrentVersion = 11;
+        private const int CurrentVersion = 12;
         private readonly IServiceProvider serviceProvider;
 
         public MigrationPath(IServiceProvider serviceProvider)
@@ -64,7 +64,8 @@ namespace Migrate_01
             }
 
             // Version 11: Introduce content drafts.
-            if (version < 11)
+            // Version 12: Fix problems with datetimes.
+            if (version < 12)
             {
                 var migration = serviceProvider.GetService<DeleteContentCollections>();