diff --git a/RocketcadManager/Assembly.cs b/RocketcadManager/Assembly.cs
index 65ac18f..d51653f 100644
--- a/RocketcadManager/Assembly.cs
+++ b/RocketcadManager/Assembly.cs
@@ -103,8 +103,7 @@ public TreeNode SubComponentTree()
 
         public override bool NameOk()
         {
-            // Assembly names must end with 00
-            return Regex.IsMatch(ComponentFileInfo.Name, @"^([0-9]{2}-)+00(\s.*)*\.(?i)SLDASM(?-i)$");
+            return Regex.IsMatch(ComponentFileInfo.Name, ConstantPaths.ValidAssemblyRegex);
         }
     }
 }
diff --git a/RocketcadManager/CadComponent.cs b/RocketcadManager/CadComponent.cs
index 2e52cf6..49e5f8e 100644
--- a/RocketcadManager/CadComponent.cs
+++ b/RocketcadManager/CadComponent.cs
@@ -46,38 +46,36 @@ public CadComponent(FileInfo fileInfo, Folder parentFolder)
             return cadInfo;
         }
 
-        public TreeNode GetNode()
+        public string GetImageKey()
         {
-            TreeNode thisNode = new TreeNode();
-            thisNode.Tag = this;
-            thisNode.Text = ComponentFileInfo.Name;
-            if (!NameOk())
+            if (!NameOk() || !LocationOk())
             {
                 if (MissingComponentError || LoadingError)
-                    SetImageKey(thisNode, "WarningErrorFile");
+                    return "WarningErrorFile";
                 else if (!HasInfo)
-                    SetImageKey(thisNode, "WarningQuestionFile");
+                    return "WarningQuestionFile";
                 else
-                    SetImageKey(thisNode, "WarningFile");
+                    return "WarningFile";
             }
             else if (MissingComponentError || LoadingError)
-                SetImageKey(thisNode, "ErrorFile");
+                return "ErrorFile";
             else if (!HasInfo)
-                SetImageKey(thisNode, "QuestionFile");
+                return "QuestionFile";
             else
-                SetImageKey(thisNode, "File");
-            return thisNode;
+                return "File";
         }
 
-        private void SetImageKey(TreeNode node, string imageKey)
+        public TreeNode GetNode()
         {
-            node.ImageKey = imageKey;
-            node.SelectedImageKey = imageKey;
-        }
+            TreeNode thisNode = new TreeNode();
+            string imageKey = GetImageKey();
 
-        public virtual bool NameOk()
-        {
-            return Regex.IsMatch(ComponentFileInfo.Name, @"^([0-9]{2}-)+[0-9]{2}(\s.*)*\.(?i)(SLDASM|SLDPRT)(?-i)$");
+            thisNode.Tag = this;
+            thisNode.Text = ComponentFileInfo.Name;
+            thisNode.ImageKey = imageKey;
+            thisNode.SelectedImageKey = imageKey;
+
+            return thisNode;
         }
 
         public int UsageCount()
@@ -104,5 +102,17 @@ public TreeNode DependancyTree()
         }
 
         public abstract void Save();
+
+        public abstract bool NameOk();
+
+        public bool LocationOk()
+        {
+            if (ParentFolder == null)
+                return true;
+            if (ConstantPaths.IgnoreTopLevelFolders && ParentFolder.ParentFolder == null)
+                return true;
+            return Regex.Match(ParentFolder.Path.Name, ConstantPaths.ParentFolderRegex).Groups[1].Value
+                == Regex.Match(ComponentFileInfo.Name, ConstantPaths.ChildFileRegex).Groups[1].Value;
+        }
     }
 }
diff --git a/RocketcadManager/Folder.cs b/RocketcadManager/Folder.cs
index 76f96f4..33641fb 100644
--- a/RocketcadManager/Folder.cs
+++ b/RocketcadManager/Folder.cs
@@ -1,4 +1,5 @@
-using System;
+using RocketcadManagerLib;
+using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.IO;
@@ -30,7 +31,7 @@ public TreeNode DirectoryTree()
             thisNode.Tag = this;
             thisNode.Text = Path.Name;
 
-            if (NameOk())
+            if (NameOk() && LocationOk())
                 SetImageKey(thisNode, "Folder");
             else
                 SetImageKey(thisNode, "WarningFolder");
@@ -61,7 +62,21 @@ public bool IsEmpty()
 
         public bool NameOk()
         {
-            return Regex.IsMatch(Path.Name, @"^([0-9]{2}-)+[0-9]{2}($|\s)");
+            // Ignore top level folders
+            if (ConstantPaths.IgnoreTopLevelFolders && ParentFolder == null)
+                return true;
+            return Regex.IsMatch(Path.Name, ConstantPaths.ValidFolderRegex);
+        }
+
+        public bool LocationOk()
+        {
+            if (ParentFolder == null)
+                return true;
+            // Ignore top level folders
+            if (ConstantPaths.IgnoreTopLevelFolders && ParentFolder.ParentFolder == null)
+                return true;
+            return Regex.Match(ParentFolder.Path.Name, ConstantPaths.ParentFolderRegex).Groups[1].Value
+                == Regex.Match(Path.Name, ConstantPaths.ChildFolderRegex).Groups[1].Value;
         }
     }
 }
diff --git a/RocketcadManager/Part.cs b/RocketcadManager/Part.cs
index 1e9a5c1..1d73542 100644
--- a/RocketcadManager/Part.cs
+++ b/RocketcadManager/Part.cs
@@ -27,8 +27,7 @@ public override void Save()
 
         public override bool NameOk()
         {
-            // Part names cannot end with 00
-            return base.NameOk() && !Regex.IsMatch(ComponentFileInfo.Name, @"^([0-9]{2}-)+00(\s.*)*\.(?i)SLDASM(?-i)$");
+            return Regex.IsMatch(ComponentFileInfo.Name, ConstantPaths.ValidPartRegex);
         }
     }
 }
diff --git a/RocketcadManager/WarningsListForm.cs b/RocketcadManager/WarningsListForm.cs
index 37cac4a..51ae810 100644
--- a/RocketcadManager/WarningsListForm.cs
+++ b/RocketcadManager/WarningsListForm.cs
@@ -29,6 +29,8 @@ private void WarningsListForm_Load(object sender, EventArgs e)
                 StringBuilder errorStrBuilder = new StringBuilder();
                 if (!cadComponent.NameOk())
                     errorStrBuilder.Append("Naming violation, ");
+                if (!cadComponent.LocationOk())
+                    errorStrBuilder.Append("Name does not match parent folder, ");
                 if (!cadComponent.HasInfo)
                     errorStrBuilder.Append("Missing info file, ");
                 if (cadComponent.MissingComponentError)
@@ -41,20 +43,7 @@ private void WarningsListForm_Load(object sender, EventArgs e)
                 string errorStr = errorStrBuilder.ToString();
 
                 // Set error icons
-                // TODO: Combine this with the similar CadComponent method
-                if (!cadComponent.NameOk())
-                {
-                    if (cadComponent.MissingComponentError || cadComponent.LoadingError)
-                        AddWarning(cadComponent, errorStr, "WarningErrorFile");
-                    else if (!cadComponent.HasInfo)
-                        AddWarning(cadComponent, errorStr, "WarningQuestionFile");
-                    else
-                        AddWarning(cadComponent, errorStr, "WarningFile");
-                }
-                else if (cadComponent.MissingComponentError || cadComponent.LoadingError)
-                    AddWarning(cadComponent, errorStr, "ErrorFile");
-                else if (!cadComponent.HasInfo)
-                    AddWarning(cadComponent, errorStr, "QuestionFile");
+                AddWarning(cadComponent, errorStr, cadComponent.GetImageKey());
             }
             foreach (ColumnHeader column in listViewWarnings.Columns)
             {
diff --git a/RocketcadManagerLib/ConstantPaths.cs b/RocketcadManagerLib/ConstantPaths.cs
index 8f3c8b1..aaf8b66 100644
--- a/RocketcadManagerLib/ConstantPaths.cs
+++ b/RocketcadManagerLib/ConstantPaths.cs
@@ -14,5 +14,14 @@ public static class ConstantPaths
 
         public static DirectoryInfo LogDir { get { return new DirectoryInfo(dataFolder + @"\logs"); } }
         public static FileInfo ConfigFile { get { return new FileInfo(dataFolder + @"\config.json"); } }
+
+        public static readonly string ValidPartRegex = @"^([0-9]{2}-)+(0[1-9]|[1-9][0-9])(\s.*)?\.(?i)SLDPRT(?-i)$";
+        public static readonly string ValidAssemblyRegex = @"^([0-9]{2}-)+00(\s.*)?\.(?i)SLDASM(?-i)$";
+        public static readonly string ValidFolderRegex = @"^([0-9]{2}-)+[0-9]{2}($|\s)";
+
+        public static readonly string ParentFolderRegex = @"^(([0-9]{2}-)+[0-9]{2})";
+        public static readonly string ChildFolderRegex = @"^([0-9]{2}(-[0-9]{2})*)-[0-9]{2}($|\s)";
+        public static readonly string ChildFileRegex = @"^([0-9]{2}(-[0-9]{2})*)-[0-9]{2}(\s.*)?\.(?i)(SLDASM|SLDPRT)(?-i)$";
+        public static readonly bool IgnoreTopLevelFolders = true;
     }
 }