diff --git a/blair-sync-rustdesk-via-ga.sh b/blair-sync-rustdesk-via-ga.sh
index 5d34460..2d7771b 100644
--- a/blair-sync-rustdesk-via-ga.sh
+++ b/blair-sync-rustdesk-via-ga.sh
@@ -115,25 +115,48 @@ def guest_ping(vmid: int) -> bool:
     return proc.returncode == 0
 
 
+def decode_ga_payload(raw) -> str:
+    if raw is None:
+        return ''
+    if isinstance(raw, bytes):
+        return raw.decode('utf-8-sig', errors='replace').strip()
+    text = str(raw).strip()
+    if not text:
+        return ''
+    if text[0] in '{[#' or 'rustdesk_id' in text or re.search(r'(?m)^\s*id\s*=', text):
+        return text.lstrip('\ufeff')
+    if re.fullmatch(r'[\d\r\n\t ]+', text):
+        return text.strip()
+    blob = ''.join(text.split())
+    if not blob:
+        return text
+    for candidate in (blob, blob + ('=' * ((4 - len(blob) % 4) % 4))):
+        try:
+            decoded = base64.b64decode(candidate, validate=False)
+            return decoded.decode('utf-8-sig', errors='replace').strip()
+        except (ValueError, binascii.Error):
+            continue
+    return text
+
+
 def decode_exec_payload(st: dict) -> tuple[str, str]:
-    out = ''
-    err = ''
-    if st.get('out-data'):
-        out = base64.b64decode(st['out-data']).decode('utf-8', errors='replace').strip()
-    if st.get('err-data'):
-        err = base64.b64decode(st['err-data']).decode('utf-8', errors='replace').strip()
+    out = decode_ga_payload(st.get('out-data'))
+    err = decode_ga_payload(st.get('err-data'))
     return out, err
 
 
 def parse_exec_result(st: dict) -> tuple[str | None, str | None]:
-    exitcode = int(st.get('exitcode', 1))
-    out, err = decode_exec_payload(st)
-    if exitcode != 0:
-        return None, err or f'guest exit {exitcode}'
-    match = re.search(r'\d{6,12}', out)
-    if not match:
-        return None, f'no id in exec output: {out!r}'
-    return match.group(0), None
+    try:
+        exitcode = int(st.get('exitcode', 1))
+        out, err = decode_exec_payload(st)
+        if exitcode != 0:
+            return None, err or out or f'guest exit {exitcode}'
+        match = re.search(r'\d{6,12}', out)
+        if not match:
+            return None, f'no id in exec output: {out!r}'
+        return match.group(0), None
+    except Exception as exc:  # noqa: BLE001
+        return None, f'exec decode error: {exc}'
 
 
 def guest_exec_text(vmid: int, command: list[str], timeout: int = 90) -> tuple[str | None, str | None]:
@@ -175,24 +198,29 @@ def guest_exec_text(vmid: int, command: list[str], timeout: int = 90) -> tuple[s
 
 
 def decode_agent_file_content(raw) -> str | None:
-    if raw is None:
-        return None
-    if isinstance(raw, bytes):
-        return raw.decode('utf-8-sig', errors='replace')
-    text = str(raw).strip()
-    if not text:
-        return None
-    # pvesh may return decoded file body (JSON/TOML/plain text).
-    if text[0] in '{[#' or 'rustdesk_id' in text or re.search(r'(?m)^\s*id\s*=', text):
-        return text.lstrip('\ufeff')
-    ascii_blob = ''.join(text.split())
-    if not ascii_blob:
-        return None
-    try:
-        decoded = base64.b64decode(ascii_blob, validate=True)
-        return decoded.decode('utf-8-sig', errors='replace')
-    except (ValueError, binascii.Error):
-        return text.lstrip('\ufeff')
+    text = decode_ga_payload(raw)
+    return text or None
+
+
+def parse_id_from_content(text: str, path: str) -> str | None:
+    if path.lower().endswith('.json'):
+        try:
+            rid = str(json.loads(text).get('rustdesk_id', '') or '').strip()
+            if re.fullmatch(r'\d{6,12}', rid):
+                return rid
+        except json.JSONDecodeError:
+            pass
+        match = re.search(r'"rustdesk_id"\s*:\s*"(\d{6,12})"', text)
+        if match:
+            return match.group(1)
+    for pattern in (
+        r'(?m)^\s*id\s*=\s*["\']?(\d{6,12})',
+        r'(?m)rustdesk_id\s*=\s*["\']?(\d{6,12})',
+    ):
+        match = re.search(pattern, text)
+        if match:
+            return match.group(1)
+    return None
 
 
 def guest_file_read(vmid: int, guest_path: str) -> tuple[str | None, str | None]:
@@ -222,24 +250,6 @@ def guest_file_read(vmid: int, guest_path: str) -> tuple[str | None, str | None]
     return None, f'file-read failed for {guest_path}'
 
 
-def parse_id_from_content(text: str, path: str) -> str | None:
-    if path.lower().endswith('.json'):
-        try:
-            rid = str(json.loads(text).get('rustdesk_id', '') or '').strip()
-            if re.fullmatch(r'\d{6,12}', rid):
-                return rid
-        except json.JSONDecodeError:
-            pass
-    for pattern in (
-        r'(?m)^\s*id\s*=\s*["\']?(\d{6,12})',
-        r'(?m)rustdesk_id\s*=\s*["\']?(\d{6,12})',
-    ):
-        match = re.search(pattern, text)
-        if match:
-            return match.group(1)
-    return None
-
-
 def powershell_encoded(script: str) -> str:
     return base64.b64encode(script.strip().encode('utf-16-le')).decode('ascii')
 
@@ -278,7 +288,7 @@ def read_rustdesk_id(vmid: int) -> tuple[str | None, str | None]:
             log(f'VM {vmid}: ID {rid} from guest exec')
         return rid, None
     errors.append(f'exec: {err}')
-    return None, errors[-1] if errors else 'unknown'
+    return None, '; '.join(errors[-4:]) if errors else 'unknown'
 
 
 def qm_description(vmid: int) -> str: