diff --git a/Models/QualcommLoader.cs b/Models/QualcommLoader.cs
index 99c1321..45ff109 100644
--- a/Models/QualcommLoader.cs
+++ b/Models/QualcommLoader.cs
@@ -53,10 +53,23 @@ namespace WPinternals
                             else
                                 Loader = new QualcommPartition(Binary);
 
-                            if ((StructuralComparisons.StructuralEqualityComparer.Equals(Loader.RootKeyHash, RootKeyHash))
-                                && (ByteOperations.FindUnicode(Loader.Binary, "QHSUSB_ARMPRG") != null)) // To detect that this is a loader, and not SBL1 or something. V1 loaders are QHSUSB_ARMPRG. V2 loaders are QHSUSB__BULK. Only V1 supported for now, because V2 only accepts signed payload.
+                            // Make sure the RootKeyHash is not blank
+                            // If the RootKeyHash is blank, this is an engineering device, and it will accept any RKH
+                            // We expect the user to know what he is doing in such case and we will ignore checks
+                            if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, new byte[RootKeyHash.Length]))
                             {
-                                Result.Add(Loader);
+                                if ((StructuralComparisons.StructuralEqualityComparer.Equals(Loader.RootKeyHash, RootKeyHash))
+                                    && (ByteOperations.FindUnicode(Loader.Binary, "QHSUSB_ARMPRG") != null)) // To detect that this is a loader, and not SBL1 or something. V1 loaders are QHSUSB_ARMPRG. V2 loaders are QHSUSB__BULK. Only V1 supported for now, because V2 only accepts signed payload.
+                                {
+                                    Result.Add(Loader);
+                                }
+                            }
+                            else
+                            {
+                                if ((ByteOperations.FindUnicode(Loader.Binary, "QHSUSB_ARMPRG") != null)) // To detect that this is a loader, and not SBL1 or something. V1 loaders are QHSUSB_ARMPRG. V2 loaders are QHSUSB__BULK. Only V1 supported for now, because V2 only accepts signed payload.
+                                {
+                                    Result.Add(Loader);
+                                }
                             }
                         }
                     }
diff --git a/ViewModels/LumiaUnlockBootloaderViewModel.cs b/ViewModels/LumiaUnlockBootloaderViewModel.cs
index ec787e4..ddd0c9d 100644
--- a/ViewModels/LumiaUnlockBootloaderViewModel.cs
+++ b/ViewModels/LumiaUnlockBootloaderViewModel.cs
@@ -373,15 +373,22 @@ namespace WPinternals
                     {
                         throw new Exception("Error: Root Key Hash could not be retrieved from the phone.");
                     }
-                    if (SBL1.RootKeyHash == null)
+
+                    // Make sure the RootKeyHash is not blank
+                    // If the RootKeyHash is blank, this is an engineering device, and it will accept any RKH
+                    // We expect the user to know what he is doing in such case and we will ignore checks
+                    if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, new byte[RootKeyHash.Length]))
                     {
-                        throw new Exception("Error: Root Key Hash could not be retrieved from FFU file.");
-                    }
-                    if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, SBL1.RootKeyHash))
-                    {
-                        LogFile.Log("Phone: " + Converter.ConvertHexToString(RootKeyHash, ""));
-                        LogFile.Log("SBL1: " + Converter.ConvertHexToString(SBL1.RootKeyHash, ""));
-                        throw new Exception("Error: Root Key Hash from phone and from FFU file do not match!");
+                        if (SBL1.RootKeyHash == null)
+                        {
+                            throw new Exception("Error: Root Key Hash could not be retrieved from FFU file.");
+                        }
+                        if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, SBL1.RootKeyHash))
+                        {
+                            LogFile.Log("Phone: " + Converter.ConvertHexToString(RootKeyHash, ""));
+                            LogFile.Log("SBL1: " + Converter.ConvertHexToString(SBL1.RootKeyHash, ""));
+                            throw new Exception("Error: Root Key Hash from phone and from FFU file do not match!");
+                        }
                     }
                 }
 
@@ -870,15 +877,22 @@ namespace WPinternals
                     {
                         throw new Exception("Error: Root Key Hash could not be retrieved from the phone.");
                     }
-                    if (SBL1.RootKeyHash == null)
+
+                    // Make sure the RootKeyHash is not blank
+                    // If the RootKeyHash is blank, this is an engineering device, and it will accept any RKH
+                    // We expect the user to know what he is doing in such case and we will ignore checks
+                    if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, new byte[RootKeyHash.Length]))
                     {
-                        throw new Exception("Error: Root Key Hash could not be retrieved from FFU file.");
-                    }
-                    if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, SBL1.RootKeyHash))
-                    {
-                        LogFile.Log("Phone: " + Converter.ConvertHexToString(RootKeyHash, ""));
-                        LogFile.Log("SBL1: " + Converter.ConvertHexToString(SBL1.RootKeyHash, ""));
-                        throw new Exception("Error: Root Key Hash from phone and from FFU file do not match!");
+                        if (SBL1.RootKeyHash == null)
+                        {
+                            throw new Exception("Error: Root Key Hash could not be retrieved from FFU file.");
+                        }
+                        if (!StructuralComparisons.StructuralEqualityComparer.Equals(RootKeyHash, SBL1.RootKeyHash))
+                        {
+                            LogFile.Log("Phone: " + Converter.ConvertHexToString(RootKeyHash, ""));
+                            LogFile.Log("SBL1: " + Converter.ConvertHexToString(SBL1.RootKeyHash, ""));
+                            throw new Exception("Error: Root Key Hash from phone and from FFU file do not match!");
+                        }
                     }
                 }