diff --git a/src/System.Management.Automation/engine/CommandCompletion/CompletionCompleters.cs b/src/System.Management.Automation/engine/CommandCompletion/CompletionCompleters.cs
index 357ce126ab..1f5c68fa31 100644
--- a/src/System.Management.Automation/engine/CommandCompletion/CompletionCompleters.cs
+++ b/src/System.Management.Automation/engine/CommandCompletion/CompletionCompleters.cs
@@ -4764,17 +4764,20 @@ namespace System.Management.Automation
                     // Save relevant info and try again to get just the names.
                     foreach (dynamic child in childItemOutput)
                     {
-                        childrenInfoTable.Add(GetChildNameFromPsObject(child, provider.ItemSeparator), child.PSIsContainer);
+                        // TryAdd is used because some providers (like SCCM) may include duplicate PSPaths in a container.
+                        _ = childrenInfoTable.TryAdd(GetChildNameFromPsObject(child, provider.ItemSeparator), child.PSIsContainer);
                     }
 
                     _ = context.Helper.CurrentPowerShell
                         .AddCommandWithPreferenceSetting("Microsoft.PowerShell.Management\\Get-ChildItem")
                         .AddParameter("LiteralPath", pathInfo.Path)
-                        .AddParameter("Name");
+                        .AddParameter("Name")
+                        .AddCommandWithPreferenceSetting("Microsoft.PowerShell.Utility\\Sort-Object")
+                        .AddParameter("Unique");
                     childItemOutput = context.Helper.ExecuteCurrentPowerShell(out _);
-                    foreach (var child in childItemOutput)
+                    foreach (PSObject child in childItemOutput)
                     {
-                        var childName = (string)child.BaseObject;
+                        string childName = (string)child.BaseObject;
                         childNameList.Add(childName);
                     }
                 }
@@ -4783,8 +4786,12 @@ namespace System.Management.Automation
                     foreach (dynamic child in childItemOutput)
                     {
                         var childName = GetChildNameFromPsObject(child, provider.ItemSeparator);
-                        childrenInfoTable.Add(childName, child.PSIsContainer);
-                        childNameList.Add(childName);
+
+                        // TryAdd is used because some providers (like SCCM) may include duplicate PSPaths in a container.
+                        if (childrenInfoTable.TryAdd(childName, child.PSIsContainer))
+                        {
+                            childNameList.Add(childName);
+                        }
                     }
                 }