diff --git a/csharp/App/Backend/Database/User.cs b/csharp/App/Backend/Database/User.cs
index ea2344aaf..3f8fef76a 100644
--- a/csharp/App/Backend/Database/User.cs
+++ b/csharp/App/Backend/Database/User.cs
@@ -1,14 +1,17 @@
 using System.Diagnostics.CodeAnalysis;
+using System.Net.Http.Headers;
 using System.Net.Mail;
 using System.Security.Cryptography;
 using System.Text;
 using System.Text.Json;
 using System.Text.Json.Nodes;
+using System.Text.RegularExpressions;
 using Flurl.Http;
 using Innovenergy.Backend.Model;
 using Innovenergy.Backend.Utils;
 using InnovEnergy.Lib.Utils;
 using SQLite;
+using ResponseExtensions = Flurl.Http.ResponseExtensions;
 
 #pragma warning disable CS0472
 #pragma warning disable CS8602
@@ -59,11 +62,42 @@ public partial class Db
         return Create(user);
     }
 
-    [UnconditionalSuppressMessage("Trimming", "IL2026:Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code", Justification = "<Pending>")]
+
+    private static Byte[] HmacSha256Digest(String message, String secret)
+    {
+        var encoding = new UTF8Encoding(); 
+        var keyBytes = encoding.GetBytes(secret);
+        var messageBytes = encoding.GetBytes(message);
+        var cryptographer = new HMACSHA256(keyBytes);
+
+        var bytes = cryptographer.ComputeHash(messageBytes);
+        return bytes;
+    }
+    
+    public String BuildSignature(String method, String path, String data, Int64 time, String secret)
+    {
+        var messageToSign = "";
+        messageToSign += method + " /v2/" + path + "\n";
+        messageToSign += data + "\n";
+
+        // query strings
+        messageToSign += "\n";
+        // headers
+        messageToSign += "\n";
+
+        messageToSign += time;
+
+        Console.WriteLine("Message to sign:\n" + messageToSign);
+
+
+        var hmac = HmacSha256Digest(messageToSign, secret);
+        return Convert.ToBase64String(hmac);
+    }
     public Object CreateAndSaveUserS3ApiKey(User user)
     {
         //EXOSCALE API URL
-        const String url = "https://api-ch-dk-2.exoscale.com/v2/access-key";
+        const String url = "https://api-ch-dk-2.exoscale.com/v2/";
+        const String path = "access-key";
         const String secret = "S2K1okphiCSNK4mzqr4swguFzngWAMb1OoSlZsJa9F0";
         const String apiKey = "EXOb98ec9008e3ec16e19d7b593";
 
@@ -80,27 +114,32 @@ public partial class Db
             instList.Add(new JsonObject {["domain"] = "sos",["resource-name"] = installation.Name,["resource-type"] = "bucket"});
         }
         
-        var jsonPayload = new JsonObject { ["name"] = user.Email, ["operations"] = new JsonArray{ "getObject", "listBucket" }, ["content"] = instList};
-        var expiration = DateTime.Now.AddSeconds(60);
+        var jsonPayload = new JsonObject { ["name"] = user.Email, ["operations"] = new JsonArray{ "list-sos-bucket", "get-sos-object" }, ["content"] = instList};
+        var stringPayload = jsonPayload.ToJsonString();
         
-        var signature = $"POST /v2/access-key\n{jsonPayload}\n\n\n{((DateTimeOffset)expiration).ToUnixTimeSeconds()}";
-        using var hmacSha256 = new HMACSHA256(Encoding.UTF8.GetBytes(secret));
-        
-        signature = Encoding.UTF8
-            .GetBytes(signature)
-            .Apply(hmacSha256.ComputeHash)
-            .Apply(Convert.ToBase64String);
+        var unixExpiration = DateTimeOffset.UtcNow.ToUnixTimeSeconds()+60;
+        var signature = BuildSignature("POST", path, stringPayload, unixExpiration , secret);
 
-        var keyJson = url
-            .WithHeader("Authorization",
-                $"EXO2-HMAC-SHA256 credential={apiKey},expires={((DateTimeOffset)expiration).ToUnixTimeSeconds()},signature={signature}");
+        var authHeader = "credential="+apiKey+",expires="+unixExpiration+",signature="+signature;
         
+        var client = new HttpClient();
+        client.DefaultRequestHeaders.Authorization =
+            new AuthenticationHeaderValue("EXO2-HMAC-SHA256", authHeader);
+
+        var content = new StringContent(stringPayload, Encoding.UTF8, "application/json");
+
+
+        var response = client.PostAsync(url+path, content).Result;
+        
+        if (response.StatusCode.ToString() != "OK")
+        {
+            return response;
+        }
+
+        var responseString = response.Content.ReadAsStringAsync().Result;
+        var newKey = Enumerable.Last(Regex.Match(responseString, "key\\\":\\\"([A-Z])\\w+").ToString().Split('"'));
+        return SetUserS3ApiKey(user, newKey);
         
-        var result = keyJson.PostJsonAsync(jsonPayload.ToString())
-            .ReceiveJson()
-            .Result;
-        return result;
-        // return SetUserS3ApiKey(user, keyJson.GetValue("key"));
     }
 
     public Result SetUserS3ApiKey(User user, String key)