diff --git a/lib/hosters.js b/lib/hosters.js
index 73b8a8d..c941144 100644
--- a/lib/hosters.js
+++ b/lib/hosters.js
@@ -196,10 +196,19 @@ function parseVoeResult(payload) {
 // Byse: { files: [{ filecode, filename, status }] }
 function parseByseResult(payload) {
   let file_code = null;
+  let perFileError = null;
 
   // Primary: files array (per official Byse API docs)
   if (Array.isArray(payload.files) && payload.files.length > 0) {
-    file_code = payload.files[0].filecode || payload.files[0].file_code;
+    const f = payload.files[0];
+    file_code = f.filecode || f.file_code || null;
+    // Byse returns HTTP 200 + msg=OK even when a specific file was rejected
+    // ("Not video file format", "Duplicate", "File too small", ...). When
+    // filecode is empty and status carries a non-OK message, that IS the
+    // actual per-file error, not a server problem.
+    if (!file_code && f.status && !/^(ok|success|done)$/i.test(String(f.status))) {
+      perFileError = String(f.status).trim();
+    }
   }
   // Fallback: result object
   if (!file_code && payload.result) {
@@ -211,6 +220,12 @@ function parseByseResult(payload) {
     }
   }
 
+  if (!file_code && perFileError) {
+    const err = new Error(`Byse lehnte Datei ab: ${perFileError}`);
+    err.fileRejected = true;
+    throw err;
+  }
+
   return {
     download_url: file_code ? `https://byse.sx/d/${file_code}` : null,
     embed_url: file_code ? `https://byse.sx/e/${file_code}` : null,
diff --git a/lib/upload-manager.js b/lib/upload-manager.js
index 9abbaa3..bd0e00c 100644
--- a/lib/upload-manager.js
+++ b/lib/upload-manager.js
@@ -56,6 +56,17 @@ class UploadManager extends EventEmitter {
     this.emit('rot-log', { ts: Date.now(), event, ...data });
   }
 
+  // File-specific rejections from the hoster: the same file will get rejected
+  // on any account, so rotation is pointless. Matches the `err.fileRejected`
+  // flag set by parsers plus known rejection phrases.
+  _isFileRejectedError(err) {
+    if (!err) return false;
+    if (err.fileRejected === true) return true;
+    if (!err.message) return false;
+    const m = String(err.message);
+    return /(Not video file format|Duplicate|Datei zu (klein|gross|groß)|File too (small|large)|Invalid file|Unsupported format|lehnte Datei ab)/i.test(m);
+  }
+
   // Transient network errors — the account is fine, the network or the
   // hoster's own backend hiccuped. Retrying on the SAME account is the right
   // move; marking it failed would wrongly poison the fallback chain. If all
@@ -530,6 +541,10 @@ class UploadManager extends EventEmitter {
           }
 
           lastError = err;
+          // File-specific rejection — re-uploading won't change the server's
+          // mind. Break out immediately; the outer file-rejected branch then
+          // records the final error without burning through 5 × 3s retries.
+          if (this._isFileRejectedError(err)) break;
           // Account-specific errors — don't waste retries on the same account,
           // jump straight to rotation.
           if (this._shouldSkipRetryOnAccountError(err)) {
@@ -569,6 +584,19 @@ class UploadManager extends EventEmitter {
         hoster: task.hoster, fileName, accountId: task.accountId,
         lastError: lastError ? lastError.message : null
       });
+      // File-specific rejection → same file will get the same verdict on
+      // every other account, rotation is pointless. Don't blacklist, don't
+      // retry siblings, just fail this file cleanly.
+      if (this._isFileRejectedError(lastError)) {
+        this._rotLog('skip-rotation-file-rejected', {
+          hoster: task.hoster, fileName, accountId: task.accountId,
+          lastError: lastError ? lastError.message : null
+        });
+        const error = lastError.message || 'Datei abgelehnt';
+        emitFinalStatus('error', { error });
+        recordFinalResult('error', { error });
+        return;
+      }
       // If the reason for failure was a transient network error we do NOT
       // blacklist the account. Other jobs on the same account in this batch
       // can still try fresh. This file just errors out for now.