diff --git a/cyberpanel.sh b/cyberpanel.sh
index acbff7055..bea973188 100644
--- a/cyberpanel.sh
+++ b/cyberpanel.sh
@@ -654,6 +654,9 @@ install_cyberpanel_direct() {
     systemctl enable mariadb 2>/dev/null || true
     systemctl enable lsws 2>/dev/null || true
     
+    # Clear any previous install temp folders so we never use stale extracted files
+    rm -rf /tmp/cyberpanel_install_* 2>/dev/null || true
+    
     # Create temporary directory for installation
     local temp_dir="/tmp/cyberpanel_install_$$"
     mkdir -p "$temp_dir"
@@ -872,6 +875,8 @@ except:
     if [ -z "$archive_url" ] || [ "$installer_url" = "https://raw.githubusercontent.com/master3395/cyberpanel/stable/cyberpanel.sh" ]; then
         archive_url="https://github.com/master3395/cyberpanel/archive/stable.tar.gz"
     fi
+    # Append cache-bust so CDNs/proxies don't serve old installer (GitHub ignores query params)
+    archive_url="${archive_url}?nocache=$(date +%s 2>/dev/null || echo 0)"
     
     curl --silent -L -o install_files.tar.gz "$archive_url" 2>/dev/null
     if [ $? -ne 0 ] || [ ! -s "install_files.tar.gz" ]; then
diff --git a/install/install_utils.py b/install/install_utils.py
index 7a5f65974..82fb0656c 100644
--- a/install/install_utils.py
+++ b/install/install_utils.py
@@ -548,6 +548,17 @@ def call(command, distro, bracket, message, log=0, do_exit=0, code=os.EX_OK, she
     Returns:
         bool: True if successful, False if failed
     """
+    # CRITICAL (first): Replace missing CyberPanel Python so old/cached installers never hit FileNotFoundError
+    if isinstance(command, str):
+        bad_path = '/usr/local/CyberPanel/bin/python'
+        if bad_path in command and not os.path.isfile(bad_path):
+            fallback = '/usr/bin/python3'
+            if not os.path.isfile(fallback):
+                fallback = '/usr/local/bin/python3'
+            if os.path.isfile(fallback):
+                command = command.replace(bad_path, fallback)
+                shell = True
+
     # Check for apt lock before running apt commands
     if 'apt-get' in command or 'apt ' in command:
         if not wait_for_apt_lock():
@@ -573,23 +584,30 @@ def call(command, distro, bracket, message, log=0, do_exit=0, code=os.EX_OK, she
             command = re.sub(r'^(\s*)(?:sudo\s+)?(mysql|mariadb)(\s)', r'\g<1>' + mysql_bin + r'\g<3>', command, count=1)
         shell = True
 
-    # CRITICAL: /usr/local/CyberPanel/bin/python often missing on fresh install; use system Python for manage.py
-    if '/usr/local/CyberPanel/bin/python' in command and not os.path.isfile('/usr/local/CyberPanel/bin/python'):
-        fallback = '/usr/bin/python3'
-        if not os.path.isfile(fallback):
-            fallback = '/usr/local/bin/python3'
-        if os.path.isfile(fallback):
-            command = command.replace('/usr/local/CyberPanel/bin/python', fallback, 1)
-        shell = True  # ensure shell so path with spaces is not split
-
     finalMessage = 'Running: %s' % (message)
     stdOut(finalMessage, log)
     count = 0
     while True:
-        if shell:
-            res = subprocess.call(command, shell=True)
-        else:
-            res = subprocess.call(shlex.split(command))
+        try:
+            if shell:
+                res = subprocess.call(command, shell=True)
+            else:
+                res = subprocess.call(shlex.split(command))
+        except FileNotFoundError as e:
+            # Old installer may pass /usr/local/CyberPanel/bin/python; retry with system python once
+            if isinstance(command, str) and '/usr/local/CyberPanel/bin/python' in command:
+                fallback = '/usr/bin/python3'
+                if not os.path.isfile(fallback):
+                    fallback = '/usr/local/bin/python3'
+                if os.path.isfile(fallback):
+                    command = command.replace('/usr/local/CyberPanel/bin/python', fallback)
+                    shell = True
+                    stdOut("Retrying with %s (CyberPanel python missing)" % fallback, log)
+                    res = subprocess.call(command, shell=True)
+                else:
+                    raise
+            else:
+                raise
 
         if resFailed(distro, res):
             count = count + 1