diff --git a/src/native/pe/PeResourceLayout.ts b/src/native/pe/PeResourceLayout.ts
index 31cb1a0b06..0364f5916f 100644
--- a/src/native/pe/PeResourceLayout.ts
+++ b/src/native/pe/PeResourceLayout.ts
@@ -101,6 +101,11 @@ export const readPeHeaders = (bytes: Buffer, fileSize = bytes.length) => {
       "unsupported",
       "DOS MZ images do not contain PE resource or certificate tables",
     );
+  if (observed.state === "declared" && observed.signature !== "PE")
+    throw new BinaryFormatFailure(
+      "unsupported",
+      `${observed.signature} images do not contain PE resource or certificate tables`,
+    );
   if (observed.state === "candidate" || observed.state === "signature-needed")
     requirePeRange(bytes, observed.offset, 24);
   if (observed.state !== "declared" || observed.signature !== "PE")
@@ -316,7 +321,10 @@ const openPeResourceTree = (
       maxEntries,
     );
   } catch (cause) {
-    if (cause instanceof ArtifactReaderFailure && cause.reason === "format")
+    if (
+      (cause instanceof ArtifactReaderFailure && cause.reason === "format") ||
+      (cause instanceof BinaryFormatFailure && cause.kind === "unsupported")
+    )
       return undefined;
     throw cause;
   }
diff --git a/src/native/pe/PeResourceParser.test.ts b/src/native/pe/PeResourceParser.test.ts
index 1981be3daf..3107908ba2 100644
--- a/src/native/pe/PeResourceParser.test.ts
+++ b/src/native/pe/PeResourceParser.test.ts
@@ -1,3 +1,4 @@
+import { dosMz, nonPeWindowsMz } from "../../domain/binaryTarget.fixture.js";
 import { ArtifactReaderFailure } from "../../artifacts/ArtifactReader.js";
 import { createHash } from "node:crypto";
 import { describe, expect, it } from "vitest";
@@ -779,3 +780,12 @@ it("keeps raw name probing separate from full resource-name alignment admission"
     message: expect.stringMatching(/unaligned.*resource name/iu),
   });
 });
+
+it.each(["DOS", "NE", "LE", "LX"] as const)(
+  "leaves %s targets outside the opportunistic PE resource probe",
+  async (format) => {
+    const bytes = format === "DOS" ? dosMz(1024) : nonPeWindowsMz(format);
+    await expect(probeSeaName(bytes)).resolves.toBe(false);
+    await expect(payloadsOf(bytes)).resolves.toEqual([]);
+  },
+);
diff --git a/src/native/pe/PeUnsupportedTargets.test.ts b/src/native/pe/PeUnsupportedTargets.test.ts
index 1e6fbc60fd..0eaa67a8b1 100644
--- a/src/native/pe/PeUnsupportedTargets.test.ts
+++ b/src/native/pe/PeUnsupportedTargets.test.ts
@@ -41,13 +41,6 @@ it.each(
         details: { operation: `inspect_pe_${operation}`, path },
       });
       expect(Buffer.compare(await readFile(path), bytes)).toBe(0);
-      await writeFile(path, Buffer.from("MZ"));
-      const malformed = await provider.inspect(input);
-      if (malformed.ok) throw new Error("Expected malformed input");
-      expect(projectAnalysisError(malformed.error)).toMatchObject({
-        code: "invalid_request",
-        category: "invalid_input",
-      });
     } finally {
       await provider.close();
     }