diff --git a/Refresh.Database/GameDatabaseContext.Photos.cs b/Refresh.Database/GameDatabaseContext.Photos.cs
index db19f290..9874595d 100644
--- a/Refresh.Database/GameDatabaseContext.Photos.cs
+++ b/Refresh.Database/GameDatabaseContext.Photos.cs
@@ -135,6 +135,13 @@ public GamePhotoSubject AddSubjectForPhoto(GamePhoto photo, int playerId, string
         return subject;
     }
 
+    public GamePhoto? GetPhotoByAnyHash(string smallHash, string mediumHash, string largeHash, string planHash)
+        => this.GamePhotosIncluded.FirstOrDefault(p => 
+            p.SmallAssetHash == smallHash ||
+            p.MediumAssetHash == mediumHash ||
+            p.LargeAssetHash == largeHash ||
+            p.PlanHash == planHash);
+
     public void RemovePhoto(GamePhoto photo)
     {
         foreach (GameUser subjectUser in this.GetUsersInPhoto(photo).ToArray())
diff --git a/Refresh.Interfaces.Game/Endpoints/PhotoEndpoints.cs b/Refresh.Interfaces.Game/Endpoints/PhotoEndpoints.cs
index 71e877b0..24bedbac 100644
--- a/Refresh.Interfaces.Game/Endpoints/PhotoEndpoints.cs
+++ b/Refresh.Interfaces.Game/Endpoints/PhotoEndpoints.cs
@@ -43,6 +43,7 @@ public Response UploadPhoto(RequestContext context, SerializedPhoto body, GameDa
         if (body.PhotoSubjects.Count > 4)
         {
             context.Logger.LogWarning(BunkumCategory.UserContent, $"Too many subjects in photo, rejecting photo upload. Uploader: {user.UserId}");
+            database.AddErrorNotification("Photo upload failed", "The photo had more than 4 players", user);
             return BadRequest;
         }
 
@@ -52,6 +53,14 @@ public Response UploadPhoto(RequestContext context, SerializedPhoto body, GameDa
             return Unauthorized;
         }
 
+        GamePhoto? existingPhoto = database.GetPhotoByAnyHash(body.SmallHash, body.MediumHash, body.LargeHash, body.PlanHash);
+        if (existingPhoto != null)
+        {
+            // TODO: show photo names in these error notifications once we start to deserialize and store plan data
+            database.AddErrorNotification("Photo upload failed", "The photo already exists on the server", user);
+            return BadRequest;
+        }
+
         List<string> hashes = [body.LargeHash, body.MediumHash, body.SmallHash];
         foreach (string hash in hashes.Distinct())
         {
diff --git a/RefreshTests.GameServer/Tests/Photos/PhotoEndpointsTests.cs b/RefreshTests.GameServer/Tests/Photos/PhotoEndpointsTests.cs
index d392a304..8774b0a1 100644
--- a/RefreshTests.GameServer/Tests/Photos/PhotoEndpointsTests.cs
+++ b/RefreshTests.GameServer/Tests/Photos/PhotoEndpointsTests.cs
@@ -7,6 +7,7 @@
 using Refresh.Database.Models.Photos;
 using Refresh.Interfaces.Game.Types.Lists;
 using Refresh.Database.Helpers;
+using System.Security.Cryptography;
 
 namespace RefreshTests.GameServer.Tests.Photos;
 
@@ -318,7 +319,7 @@ public void CantDeleteInvalidPhoto()
         Assert.That(message.StatusCode, Is.EqualTo(NotFound));
     }
     
-        [Test]
+    [Test]
     public void CantDeleteOthersPhoto()
     {
         using TestContext context = this.GetServer();
@@ -381,4 +382,130 @@ public void CantDeleteOthersPhoto()
         response = message.Content.ReadAsXML<SerializedPhotoList>();
         Assert.That(response.Items, Has.Count.EqualTo(1));
     }
+
+    [Test]
+    public void CannotUploadPhotoIfDuplicateImage()
+    {
+        using TestContext context = this.GetServer();
+        GameUser user = context.CreateUser();
+        using HttpClient client = context.GetAuthenticatedClient(TokenType.Game, user);
+
+        //Upload our """photo"""
+        HttpResponseMessage message = client.PostAsync($"/lbp/upload/{TEST_ASSET_HASH}", new ReadOnlyMemoryContent(TestAsset)).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+
+        //Upload our """plan"""
+        ReadOnlySpan<byte> planData = "PLNbum"u8;
+        string planHash = HexHelper.BytesToHexString(SHA1.HashData(planData));
+        message = client.PostAsync("/lbp/upload/" + planHash, new ByteArrayContent(planData.ToArray())).Result;
+
+        //Upload another """plan"""
+        ReadOnlySpan<byte> anotherPlanData = "PLNble"u8;
+        string anotherPlanHash = HexHelper.BytesToHexString(SHA1.HashData(anotherPlanData));
+        message = client.PostAsync("/lbp/upload/" + anotherPlanHash, new ByteArrayContent(anotherPlanData.ToArray())).Result;
+        
+        SerializedPhoto photo1 = new()
+        {
+            Timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+            AuthorName = user.Username,
+            SmallHash = TEST_ASSET_HASH,
+            MediumHash = TEST_ASSET_HASH,
+            LargeHash = TEST_ASSET_HASH,
+            PlanHash = planHash,
+            Level = new SerializedPhotoLevel
+            {
+                LevelId = 0,
+                Title = "",
+                Type = "pod",
+            }
+        };
+        
+        //Upload photo once
+        message = client.PostAsync($"/lbp/uploadPhoto", new StringContent(photo1.AsXML())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+
+        //Upload photo again (different plan hash)
+        SerializedPhoto photo2 = new()
+        {
+            Timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+            AuthorName = user.Username,
+            SmallHash = TEST_ASSET_HASH,
+            MediumHash = TEST_ASSET_HASH,
+            LargeHash = TEST_ASSET_HASH,
+            PlanHash = anotherPlanHash,
+            Level = new SerializedPhotoLevel
+            {
+                LevelId = 0,
+                Title = "",
+                Type = "pod",
+            }
+        };
+        message = client.PostAsync($"/lbp/uploadPhoto", new StringContent(photo2.AsXML())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(BadRequest));
+        Assert.That(context.Database.GetNotificationCountByUser(user), Is.EqualTo(1));
+    }
+
+    [Test]
+    public void CannotUploadPhotoIfDuplicatePlan()
+    {
+        using TestContext context = this.GetServer();
+        GameUser user = context.CreateUser();
+        using HttpClient client = context.GetAuthenticatedClient(TokenType.Game, user);
+
+        //Upload our """photo"""
+        HttpResponseMessage message = client.PostAsync($"/lbp/upload/{TEST_ASSET_HASH}", new ReadOnlyMemoryContent(TestAsset)).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+
+        //Upload another """photo"""
+        ReadOnlySpan<byte> anotherTextureData = "TEX r"u8;
+        string anotherTextureHash = HexHelper.BytesToHexString(SHA1.HashData(anotherTextureData));
+        message = client.PostAsync("/lbp/upload/" + anotherTextureHash, new ByteArrayContent(anotherTextureData.ToArray())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+
+        //Upload our """plan"""
+        ReadOnlySpan<byte> planData = "PLNb"u8;
+        string planHash = HexHelper.BytesToHexString(SHA1.HashData(planData));
+        message = client.PostAsync("/lbp/upload/" + planHash, new ByteArrayContent(planData.ToArray())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+        
+        SerializedPhoto photo1 = new()
+        {
+            Timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+            AuthorName = user.Username,
+            SmallHash = TEST_ASSET_HASH,
+            MediumHash = TEST_ASSET_HASH,
+            LargeHash = TEST_ASSET_HASH,
+            PlanHash = planHash,
+            Level = new SerializedPhotoLevel
+            {
+                LevelId = 0,
+                Title = "",
+                Type = "pod",
+            }
+        };
+        
+        //Upload photo once
+        message = client.PostAsync($"/lbp/uploadPhoto", new StringContent(photo1.AsXML())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(OK));
+
+        //Upload photo again (different image hashes)
+        SerializedPhoto photo2 = new()
+        {
+            Timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+            AuthorName = user.Username,
+            SmallHash = anotherTextureHash,
+            MediumHash = anotherTextureHash,
+            LargeHash = anotherTextureHash,
+            PlanHash = planHash,
+            Level = new SerializedPhotoLevel
+            {
+                LevelId = 0,
+                Title = "",
+                Type = "pod",
+            }
+        };
+        message = client.PostAsync($"/lbp/uploadPhoto", new StringContent(photo2.AsXML())).Result;
+        Assert.That(message.StatusCode, Is.EqualTo(BadRequest));
+        Assert.That(context.Database.GetNotificationCountByUser(user), Is.EqualTo(1));
+    }
 }
\ No newline at end of file