diff --git a/Knossos.NET/Models/Nebula.cs b/Knossos.NET/Models/Nebula.cs
index 8c47bdc7..ae4b0746 100644
--- a/Knossos.NET/Models/Nebula.cs
+++ b/Knossos.NET/Models/Nebula.cs
@@ -804,9 +804,9 @@ private enum ApiMethod
                                     return await ApiCall(resourceUrl, data, needsLogIn, timeoutSeconds, method);
                                 }
                                 /* Upload/Update/delete Mod Timeout Hack */
-                                if(response.StatusCode.ToString() == "GatewayTimeout" && (resourceUrl == "mod/release" || resourceUrl == "mod/release/update" || resourceUrl == "mod/release/delete"))
+                                if(response.StatusCode.ToString() == "GatewayTimeout" && (resourceUrl == "mod/release" || resourceUrl == "mod/release/update" || resourceUrl == "mod/release/delete" || resourceUrl == "multiupload/finish"))
                                 {
-                                    Log.Add(Log.LogSeverity.Warning, "Nebula.ApiCall(" + resourceUrl + ")", "During mod/release request a GatewayTimeout was recieved. This is a known issue with Nebula and while Knet handles this" +
+                                    Log.Add(Log.LogSeverity.Warning, "Nebula.ApiCall(" + resourceUrl + ")", "A GatewayTimeout was received. This is a known issue with Nebula and while Knet handles this" +
                                         " as a success there is not an actual way to know if the api call was really successfull.");
                                     var reply = new ApiReply();
                                     reply.result = true;
@@ -1844,14 +1844,12 @@ public async Task<bool> Upload()
                     }
                 });
 
-                completed = true;
+                if (cancellationTokenSource.IsCancellationRequested)
+                    throw new TaskCanceledException();
 
                 if (progressCallback != null)
                     progressCallback.Invoke("Verifying Upload...", maxProgress, maxProgress);
 
-                if (cancellationTokenSource.IsCancellationRequested)
-                    throw new TaskCanceledException();
-
                 int attempt = 1;
                 do
                 {
@@ -1860,10 +1858,11 @@ public async Task<bool> Upload()
                     if (verified && progressCallback != null)
                         progressCallback.Invoke("Verify: " + verified, maxProgress, maxProgress);
 
-                    if (!verified && progressCallback != null && attempt <= maxUploadRetries)
+                    if (!verified && attempt <= maxUploadRetries)
                     {
                         Log.Add(Log.LogSeverity.Warning, "Nebula.Upload", "File failed nebula upload verify, retrying: " + fileFullPath);
-                        progressCallback.Invoke("Verify: Failed, Retrying... Retry #" + attempt, maxProgress, maxProgress);
+                        if (progressCallback != null)
+                            progressCallback.Invoke("Verify: Failed, Retrying... Retry #" + attempt, maxProgress, maxProgress);
                         await Task.Delay(2000);
                     }
 
@@ -1875,37 +1874,87 @@ public async Task<bool> Upload()
             /// <summary>
             /// Call to complete the upload process
             /// Nebula will check the complete file checksum here
+            /// Retries with exponential backoff, checking server state between attempts
             /// </summary>
             /// <returns>true if everything is fine, false otherwise</returns>
             private async Task<bool> Finish()
             {
-                var data = new MultipartFormDataContent()
-                {
-                    { new StringContent(fileChecksum!), "id" },
-                    { new StringContent(fileChecksum!), "checksum" },
-                    { new StringContent("None"), "content_checksum" },
-                    { new StringContent("None"), "vp_checksum" }
-                };
+                const int maxFinishRetries = 3;
 
-                var reply = await ApiCall("multiupload/finish", data, true, 160);
-                if (reply.HasValue)
+                for (int attempt = 1; attempt <= maxFinishRetries; attempt++)
                 {
-                    if (!reply.Value.result)
+                    var data = new MultipartFormDataContent()
                     {
-                        Log.Add(Log.LogSeverity.Error, "MultipartUploader.Finish", "Unable to multi part upload process to Nebula. Reason: " + reply.Value.reason);
-                        if (progressCallback != null)
-                            progressCallback.Invoke("Verify: " + reply.Value.reason, 0, 1);
+                        { new StringContent(fileChecksum!), "id" },
+                        { new StringContent(fileChecksum!), "checksum" },
+                        { new StringContent("None"), "content_checksum" },
+                        { new StringContent("None"), "vp_checksum" }
+                    };
+
+                    var reply = await ApiCall("multiupload/finish", data, true, 160);
+                    if (reply.HasValue)
+                    {
+                        if (reply.Value.result)
+                        {
+                            Log.Add(Log.LogSeverity.Information, "MultipartUploader.Finish", "Multiupload: File uploaded to Nebula! " + fileFullPath);
+                            completed = true;
+                            return true;
+                        }
+                        else
+                        {
+                            Log.Add(Log.LogSeverity.Error, "MultipartUploader.Finish", "Unable to complete multipart upload to Nebula. Reason: " + reply.Value.reason);
+                            if (progressCallback != null)
+                                progressCallback.Invoke("Verify: " + reply.Value.reason, 0, 1);
+                            completed = false;
+                            return false;  // Definitive failure (e.g. checksum mismatch) — don't retry
+                        }
                     }
-                    else
+
+                    // reply is null — network error, client timeout, or similar
+                    Log.Add(Log.LogSeverity.Warning, "MultipartUploader.Finish",
+                        "Finish attempt " + attempt + " of " + maxFinishRetries + " got no valid reply. Checking server state...");
+
+                    await Task.Delay(2000 * attempt);  // Exponential backoff
+
+                    // Check if the server actually completed the upload
+                    if (await CheckUploadDone())
                     {
-                        Log.Add(Log.LogSeverity.Information, "MultipartUploader.Finish", "Multiupload: File uploaded to Nebula! " + fileFullPath);
+                        Log.Add(Log.LogSeverity.Information, "MultipartUploader.Finish",
+                            "Server confirmed upload is complete after finish attempt " + attempt);
+                        completed = true;
+                        return true;
+                    }
+
+                    if (attempt < maxFinishRetries)
+                    {
+                        Log.Add(Log.LogSeverity.Warning, "MultipartUploader.Finish",
+                            "Server says upload not done. Retrying finish (attempt " + (attempt + 1) + ")...");
                     }
-                    completed = reply.Value.result;
-                    return reply.Value.result;
                 }
+
+                Log.Add(Log.LogSeverity.Error, "MultipartUploader.Finish",
+                    "All finish attempts exhausted for " + fileFullPath);
+                completed = false;
                 return false;
             }
 
+            /// <summary>
+            /// Calls multiupload/start to check if the server has already marked this upload as done.
+            /// Used to verify whether a timed-out finish call actually succeeded server-side.
+            /// </summary>
+            private async Task<bool> CheckUploadDone()
+            {
+                var data = new MultipartFormDataContent()
+                {
+                    { new StringContent(fileChecksum!), "id" },
+                    { new StringContent(fileLenght.ToString()), "size" },
+                    { new StringContent(fileParts.Count().ToString()), "parts" }
+                };
+
+                var reply = await ApiCall("multiupload/start", data, true);
+                return reply.HasValue && reply.Value.done;
+            }
+
             /// <summary>
             /// Starts the file upload process
             /// Here we pass file checksum, file size and number of parts to Nebula
@@ -2076,7 +2125,7 @@ public async Task<bool> Verify()
                         { new StringContent(partChecksum), "checksum" },
                     };
 
-                    var reply = await ApiCall("multiupload/verify_part", data, true);
+                    var reply = await ApiCall("multiupload/verify_part", data, true, 120);
                     if (reply.HasValue)
                     {
                         if (!reply.Value.result)