diff --git a/src/main/download-completion.ts b/src/main/download-completion.ts
index 13fdc30..d0a52f8 100644
--- a/src/main/download-completion.ts
+++ b/src/main/download-completion.ts
@@ -72,6 +72,22 @@ export function planDownloadCompletion(args: {
   };
 }
 
+export function reconcileFinalizedSize(
+  streamedBytes: number,
+  statSize: number,
+  preAllocated: boolean
+): number {
+  const streamed = Math.max(0, Math.floor(Number(streamedBytes) || 0));
+  if (!Number.isFinite(statSize) || statSize < 0) {
+    return streamed;
+  }
+  const onDisk = Math.floor(statSize);
+  if (preAllocated && onDisk > streamed) {
+    return streamed;
+  }
+  return onDisk;
+}
+
 export function validateDownloadedFileCompletion(args: {
   actualBytes: number;
   plan: DownloadCompletionPlan;
diff --git a/src/main/download-manager.ts b/src/main/download-manager.ts
index 01dcee7..7f0f249 100644
--- a/src/main/download-manager.ts
+++ b/src/main/download-manager.ts
@@ -51,7 +51,7 @@ function releaseTlsSkip(): void {
   }
 }
 import { cleanupCancelledPackageArtifactsAsync, removeDownloadLinkArtifacts, removeSampleArtifacts } from "./cleanup";
-import { planDownloadCompletion, validateDownloadedFileCompletion } from "./download-completion";
+import { planDownloadCompletion, reconcileFinalizedSize, validateDownloadedFileCompletion } from "./download-completion";
 import { AllDebridWebUnrestrictor, BestDebridWebUnrestrictor, DebridService, MegaWebUnrestrictor, RealDebridWebUnrestrictor, checkRapidgatorOnline, fetchAllDebridHostInfo, getAvailableDebridLinkApiKeys, getAvailableMegaDebridAccounts, getMegaDebridAccountCooldownState, pruneExpiredDebridLinkRuntimeState, pruneExpiredMegaDebridRuntimeState } from "./debrid";
 import { cleanupArchives, clearExtractResumeState, collectArchiveCleanupTargets, detectArchiveSignature, extractPackageArchives, findArchiveCandidates, hasAnyFilesRecursive, removeEmptyDirectoryTree, resetExtractorCachesForPasswordChange, type ExtractArchiveFailureInfo } from "./extractor";
 import { validateFileAgainstManifest } from "./integrity";
@@ -10357,13 +10357,15 @@ export class DownloadManager extends EventEmitter {
 
         try {
           const finalizedStat = await fs.promises.stat(effectiveTargetPath);
-          if (Number.isFinite(finalizedStat.size) && finalizedStat.size >= 0 && finalizedStat.size !== written) {
+          const reconciledSize = reconcileFinalizedSize(written, finalizedStat.size, preAllocated);
+          if (reconciledSize !== written) {
             logAttemptEvent("WARN", "Dateigroesse nach Stream-Abschluss korrigiert", {
               attempt,
               previousWritten: written,
-              statSize: finalizedStat.size
+              statSize: finalizedStat.size,
+              reconciledSize
             });
-            written = finalizedStat.size;
+            written = reconciledSize;
           }
         } catch {
         }
diff --git a/tests/download-completion.test.ts b/tests/download-completion.test.ts
index b5b7f6a..72b9ccf 100644
--- a/tests/download-completion.test.ts
+++ b/tests/download-completion.test.ts
@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { planDownloadCompletion, validateDownloadedFileCompletion } from "../src/main/download-completion";
+import { planDownloadCompletion, reconcileFinalizedSize, validateDownloadedFileCompletion } from "../src/main/download-completion";
 
 describe("download-completion", () => {
   describe("planDownloadCompletion", () => {
@@ -58,4 +58,33 @@ describe("download-completion", () => {
       expect(result.ok).toBe(false);
     });
   });
+
+  describe("reconcileFinalizedSize", () => {
+    it("keeps the streamed count for a pre-allocated file whose on-disk size is the zero-padding (corruption guard)", () => {
+      expect(reconcileFinalizedSize(300_000_000, 1_000_000_000, true)).toBe(300_000_000);
+    });
+
+    it("shrinks to the on-disk size when a pre-allocated file is genuinely short (real partial write)", () => {
+      expect(reconcileFinalizedSize(500, 300, true)).toBe(300);
+    });
+
+    it("reconciles in both directions for a non-pre-allocated file (stat is authoritative)", () => {
+      expect(reconcileFinalizedSize(300, 1000, false)).toBe(1000);
+      expect(reconcileFinalizedSize(1000, 300, false)).toBe(300);
+    });
+
+    it("returns the streamed count unchanged when the stat is invalid", () => {
+      expect(reconcileFinalizedSize(1234, Number.NaN, true)).toBe(1234);
+      expect(reconcileFinalizedSize(1234, -1, false)).toBe(1234);
+    });
+
+    it("is a no-op when on-disk size already equals the streamed count", () => {
+      expect(reconcileFinalizedSize(777, 777, true)).toBe(777);
+      expect(reconcileFinalizedSize(777, 777, false)).toBe(777);
+    });
+
+    it("does not block legitimate overshoot on a pre-allocated file (server sent more than pre-alloc)", () => {
+      expect(reconcileFinalizedSize(900, 900, true)).toBe(900);
+    });
+  });
 });