diff --git a/aider/main.py b/aider/main.py
index 9929213ec..a5b3e5242 100644
--- a/aider/main.py
+++ b/aider/main.py
@@ -372,13 +372,40 @@ def main(argv=None, input=None, output=None, force_git_root=None, return_coder=F
     default_config_files.reverse()
 
     parser = get_parser(default_config_files, git_root)
-    args, unknown = parser.parse_known_args(argv)
+
+    try:
+        args, unknown = parser.parse_known_args(argv)
+    except AttributeError as e:
+        if "'bool' object has no attribute 'strip'" in str(e):
+            io.tool_error("Configuration error detected.")
+            io.tool_output("It seems you have 'yes:' in one of your configuration files.")
+            io.tool_output("Please replace 'yes:' with 'yes-always:' in the relevant .aider.conf.yml file.")
+            io.tool_output("Configuration files are searched for in this order:")
+            for config_file in default_config_files:
+                io.tool_output(f"  - {config_file}")
+            io.tool_output("For more information, refer to the aider documentation on configuration.")
+            return 1
+        else:
+            raise
 
     # Load the .env file specified in the arguments
     loaded_dotenvs = load_dotenv_files(git_root, args.env_file, args.encoding)
 
     # Parse again to include any arguments that might have been defined in .env
-    args = parser.parse_args(argv)
+    try:
+        args = parser.parse_args(argv)
+    except AttributeError as e:
+        if "'bool' object has no attribute 'strip'" in str(e):
+            io.tool_error("Configuration error detected.")
+            io.tool_output("It seems you have 'yes:' in one of your configuration files.")
+            io.tool_output("Please replace 'yes:' with 'yes-always:' in the relevant .aider.conf.yml file.")
+            io.tool_output("Configuration files are searched for in this order:")
+            for config_file in default_config_files:
+                io.tool_output(f"  - {config_file}")
+            io.tool_output("For more information, refer to the aider documentation on configuration.")
+            return 1
+        else:
+            raise
 
     if not args.verify_ssl:
         import httpx