diff --git a/imapbackup38.py b/imapbackup38.py
index 92ef6bf..c792529 100644
--- a/imapbackup38.py
+++ b/imapbackup38.py
@@ -398,8 +398,9 @@ def print_usage():
     print (" -d DIR --mbox-dir=DIR         Write mbox files to directory. (defaults to cwd)")
     print (" -a --append-to-mboxes         Append new messages to mbox files. (default)")
     print (" -y --yes-overwrite-mboxes     Overwite existing mbox files instead of appending.")
-    print (" -f FOLDERS --folders=FOLDERS  Specify which folders to include. Overrides --exclude-folders. Comma separated list.")
-    print (" --exclude-folders=FOLDERS     Specify which folders to exclude. Overridden by --folders. Comma separated list.")
+    print (" -f FOLDERS --folders=FOLDERS  Specify which folders to include. Comma separated list.")
+    print (" --exclude-folders=FOLDERS     Specify which folders to exclude. Comma separated list.")
+    print ("                               You cannot use both --folders and --exclude-folders.")
     print (" -e --ssl                      Use SSL.  Port defaults to 993.")
     print (" -k KEY --key=KEY              PEM private key file for SSL.  Specify cert, too.")
     print (" -c CERT --cert=CERT           PEM certificate chain for SSL.  Specify key, too.")
@@ -644,18 +645,19 @@ def main():
     """Main entry point"""
     try:
         config = get_config()
+        if config.get('folders') and config.get('exclude-folders'):
+            print("ERROR: You cannot use both --folders and --exclude-folders at the same time")
+            sys.exit(2)
         server = connect_and_login(config)
         names = get_names(server,config['thunderbird'],config['nospinner'])
         exclude_folders = []
         if config.get('folders'):
-            # Takes precedence over --exclude-folders
             dirs = list(map(lambda x: x.strip(), config.get('folders').split(',')))
             if config['thunderbird']:
                 dirs = [i.replace("Inbox", "INBOX", 1) if i.startswith("Inbox") else i
                         for i in dirs]
             names = list(filter(lambda x: x[0] in dirs, names))
         elif config.get('exclude-folders'):
-            # Use --exclude-folders option only when --folders is not set
             exclude_folders = list(map(lambda x: x.strip(), config.get('exclude-folders').split(',')))
 
         basedir = config.get('basedir')