diff --git a/Azaion.Common/BusinessException.cs b/Azaion.Common/BusinessException.cs
index a149aa1..5ec5268 100644
--- a/Azaion.Common/BusinessException.cs
+++ b/Azaion.Common/BusinessException.cs
@@ -35,10 +35,10 @@ public enum ExceptionEnum
 
     WrongEmail = 37,
 
-    [Description("HardwareInfo mismatch! You are not authorized to access this resource from this hardware.")]
+    [Description("Hardware mismatch! You are not authorized to access this resource from this hardware.")]
     HardwareIdMismatch = 40,
 
-    [Description("HardwareInfo should contain information about this hardware.")]
+    [Description("Hardware should be not empty.")]
     BadHardware = 45,
 
     [Description("Wrong resource file name.")]
diff --git a/Azaion.Common/Entities/HardwareInfo.cs b/Azaion.Common/Entities/HardwareInfo.cs
deleted file mode 100644
index c135e20..0000000
--- a/Azaion.Common/Entities/HardwareInfo.cs
+++ /dev/null
@@ -1,9 +0,0 @@
-namespace Azaion.Common.Entities;
-
-public class HardwareInfo
-{
-    public string CPU        { get; set; } = null!;
-    public string GPU        { get; set; } = null!;
-    public string MacAddress { get; set; } = null!;
-    public string Memory     { get; set; } = null!;
-}
\ No newline at end of file
diff --git a/Azaion.Common/Requests/GetResourceRequest.cs b/Azaion.Common/Requests/GetResourceRequest.cs
index a2cf14e..4e434cd 100644
--- a/Azaion.Common/Requests/GetResourceRequest.cs
+++ b/Azaion.Common/Requests/GetResourceRequest.cs
@@ -1,4 +1,3 @@
-using Azaion.Common.Entities;
 using FluentValidation;
 
 namespace Azaion.Common.Requests;
@@ -6,7 +5,7 @@ namespace Azaion.Common.Requests;
 public class GetResourceRequest
 {
     public string Password { get; set; } = null!;
-    public HardwareInfo Hardware { get; set; } = null!;
+    public string Hardware { get; set; } = null!;
     public string FileName { get; set; } = null!;
 }
 
diff --git a/Azaion.Services/Security.cs b/Azaion.Services/Security.cs
index 294682d..033f89d 100644
--- a/Azaion.Services/Security.cs
+++ b/Azaion.Services/Security.cs
@@ -11,8 +11,8 @@ public static class Security
     public static string ToHash(this string str) =>
         Convert.ToBase64String(SHA384.HashData(Encoding.UTF8.GetBytes(str)));
 
-    public static string GetHWHash(HardwareInfo hardware) =>
-        $"Azaion_{hardware.MacAddress}_{hardware.CPU}_{hardware.GPU}".ToHash();
+    public static string GetHWHash(string hardware) =>
+        $"Azaion_{hardware}_%$$$)0_".ToHash();
 
     public static string GetApiEncryptionKey(string email, string password, string? hardwareHash) =>
         $"{email}-{password}-{hardwareHash}-#%@AzaionKey@%#---".ToHash();
diff --git a/Azaion.Services/UserService.cs b/Azaion.Services/UserService.cs
index 0e16c20..950cc1d 100644
--- a/Azaion.Services/UserService.cs
+++ b/Azaion.Services/UserService.cs
@@ -13,7 +13,7 @@ public interface IUserService
     Task RegisterUser(RegisterUserRequest request, CancellationToken cancellationToken = default);
     Task<User> ValidateUser(LoginRequest request, CancellationToken cancellationToken = default);
     Task<User?> GetByEmail(string? email, CancellationToken cancellationToken = default);
-    Task UpdateHardware(string email, HardwareInfo? hardwareInfo = null, CancellationToken cancellationToken = default);
+    Task UpdateHardware(string email, string? hardware = null, CancellationToken cancellationToken = default);
     Task UpdateQueueOffsets(string email, UserQueueOffsets queueOffsets, CancellationToken cancellationToken = default);
     Task<IEnumerable<User>> GetUsers(string? searchEmail, RoleEnum? searchRole, CancellationToken cancellationToken);
     Task<string> CheckHardwareHash(User user, GetResourceRequest request);
@@ -39,10 +39,15 @@ public class UserService(IDbFactory dbFactory, ICache cache) : IUserService
         });
     }
 
-    public async Task<User?> GetByEmail(string? email, CancellationToken cancellationToken = default) =>
-        await cache.GetFromCacheAsync(User.GetCacheKey(email),
+    public async Task<User?> GetByEmail(string? email, CancellationToken cancellationToken = default)
+    {
+        if (string.IsNullOrWhiteSpace(email)) throw new ArgumentNullException(nameof(email));
+
+        return await cache.GetFromCacheAsync(User.GetCacheKey(email),
             async () => await dbFactory.Run(async db =>
                 await db.Users.FirstOrDefaultAsync(x => x.Email == email, cancellationToken)));
+    }
+
 
     public async Task<User> ValidateUser(LoginRequest request, CancellationToken cancellationToken = default) =>
         await dbFactory.Run(async db =>
@@ -58,17 +63,12 @@ public class UserService(IDbFactory dbFactory, ICache cache) : IUserService
         });
 
 
-    public async Task UpdateHardware(string email, HardwareInfo? hardware = null, CancellationToken cancellationToken = default)
+    public async Task UpdateHardware(string email, string? hardware = null, CancellationToken cancellationToken = default)
     {
         await dbFactory.RunAdmin(async db =>
         {
-            var hardwareStr = hardware == null ? "" : JsonConvert.SerializeObject(hardware);
-
             await db.Users.UpdateAsync(x => x.Email == email,
-                u => new User
-                {
-                    Hardware = hardwareStr
-                }, token: cancellationToken);
+                u => new User { Hardware = hardware }, token: cancellationToken);
         });
         cache.Invalidate(User.GetCacheKey(email));
     }
@@ -111,8 +111,7 @@ public class UserService(IDbFactory dbFactory, ICache cache) : IUserService
             return requestHWHash;
         }
 
-        var userHW = JsonConvert.DeserializeObject<HardwareInfo>(user.Hardware);
-        var userHWHash = Security.GetHWHash(userHW!);
+        var userHWHash = Security.GetHWHash(user.Hardware);
         if (userHWHash != requestHWHash)
             throw new BusinessException(ExceptionEnum.HardwareIdMismatch);
         return userHWHash;