diff --git a/rpxy-lib/src/message_handler/handler_main.rs b/rpxy-lib/src/message_handler/handler_main.rs
index 5fb978d..c46ac85 100644
--- a/rpxy-lib/src/message_handler/handler_main.rs
+++ b/rpxy-lib/src/message_handler/handler_main.rs
@@ -143,6 +143,12 @@ where
 
     // Upgrade in request header
     let upgrade_in_request = extract_upgrade(req.headers());
+    if upgrade_in_request.is_some() && req.version() != http::Version::HTTP_11 {
+      return Err(HttpError::FailedToUpgrade(format!(
+        "Unsupported HTTP version: {:?}",
+        req.version()
+      )));
+    }
     // let request_upgraded = req.extensions_mut().remove::<hyper::upgrade::OnUpgrade>();
     let req_on_upgrade = hyper::upgrade::on(&mut req);
 
diff --git a/rpxy-lib/src/message_handler/handler_manipulate_messages.rs b/rpxy-lib/src/message_handler/handler_manipulate_messages.rs
index 529a17a..a0b37e0 100644
--- a/rpxy-lib/src/message_handler/handler_manipulate_messages.rs
+++ b/rpxy-lib/src/message_handler/handler_manipulate_messages.rs
@@ -177,8 +177,11 @@ where
         .headers_mut()
         .insert(header::CONNECTION, HeaderValue::from_static("upgrade"));
     }
+    if upgrade.is_none() {
+      // can update request line i.e., http version, only if not upgrade (http 1.1)
+      update_request_line(req, upstream_chosen, upstream_candidates)?;
+    }
 
-    update_request_line(req, upstream_chosen, upstream_candidates)?;
 
     Ok(context)
   }
diff --git a/rpxy-lib/src/message_handler/http_result.rs b/rpxy-lib/src/message_handler/http_result.rs
index 691c087..98cdb45 100644
--- a/rpxy-lib/src/message_handler/http_result.rs
+++ b/rpxy-lib/src/message_handler/http_result.rs
@@ -8,8 +8,8 @@ pub(crate) type HttpResult<T> = std::result::Result<T, HttpError>;
 /// Describes things that can go wrong in the forwarder
 #[derive(Debug, Error)]
 pub enum HttpError {
-  #[error("No host is give nin request header")]
-  NoHostInRequestHeader,
+  // #[error("No host is give in request header")]
+  // NoHostInRequestHeader,
   #[error("Invalid host in request header")]
   InvalidHostInRequestHeader,
   #[error("SNI and Host header mismatch")]
@@ -43,7 +43,7 @@ pub enum HttpError {
 impl From<HttpError> for StatusCode {
   fn from(e: HttpError) -> StatusCode {
     match e {
-      HttpError::NoHostInRequestHeader => StatusCode::BAD_REQUEST,
+      // HttpError::NoHostInRequestHeader => StatusCode::BAD_REQUEST,
       HttpError::InvalidHostInRequestHeader => StatusCode::BAD_REQUEST,
       HttpError::SniHostInconsistency => StatusCode::MISDIRECTED_REQUEST,
       HttpError::NoMatchingBackendApp => StatusCode::SERVICE_UNAVAILABLE,