diff --git a/src/SIL.XForge.Scripture/Services/MachineProjectService.cs b/src/SIL.XForge.Scripture/Services/MachineProjectService.cs
index ac636f9db0..99e5f608b6 100644
--- a/src/SIL.XForge.Scripture/Services/MachineProjectService.cs
+++ b/src/SIL.XForge.Scripture/Services/MachineProjectService.cs
@@ -1312,10 +1312,12 @@ CancellationToken cancellationToken
         }
 
         // Remove the corpora and files
-        foreach (
-            (string corpusId, _) in projectSecret.ServalData?.Corpora?.Where(c => c.Value.PreTranslate == preTranslate)
-                ?? []
-        )
+        string[] corpusIds =
+            projectSecret
+                .ServalData?.Corpora?.Where(c => c.Value.PreTranslate == preTranslate)
+                .Select(c => c.Key)
+                .ToArray() ?? [];
+        foreach (string corpusId in corpusIds)
         {
             // Delete the corpus
             try