diff --git a/eng/common/TestResources/New-TestResources.ps1 b/eng/common/TestResources/New-TestResources.ps1
index fa75730dcd2d..bb83ec15951b 100644
--- a/eng/common/TestResources/New-TestResources.ps1
+++ b/eng/common/TestResources/New-TestResources.ps1
@@ -190,7 +190,7 @@ try {
         $BaseName = 't' + (New-Guid).ToString('n').Substring(0, 16)
         Log "Generated base name '$BaseName' for CI build"
     } elseif (!$BaseName) {
-        $BaseName = "$UserName$ServiceDirectory"
+        $BaseName = "$UserName$ServiceDirectory" + (New-Guid).ToString('n').Substring(0, 4)
         Log "BaseName was not set. Using default base name '$BaseName'"
     }