diff --git a/frappe/public/js/frappe/upload.js b/frappe/public/js/frappe/upload.js
index ca2ed264ed..4f27c3db3c 100644
--- a/frappe/public/js/frappe/upload.js
+++ b/frappe/public/js/frappe/upload.js
@@ -310,8 +310,7 @@ frappe.upload = {
 
 		const file_not_big_enough = fileobj.size <= 24576;
 
-		if (!frappe.socketio || opts.no_socketio ||
-				frappe.flags.no_socketio || file_not_big_enough) {
+		if (!frappe.socketio || opts.no_socketio || frappe.flags.no_socketio || frappe.boot.disable_async || file_not_big_enough) {
 			upload_with_filedata();
 			return;
 		} else {
@@ -327,24 +326,26 @@ frappe.upload = {
 		}
 
 		var upload_through_socketio = function() {
-			frappe.socketio.uploader.start({
-				file: fileobj,
-				filename: args.filename,
-				is_private: args.is_private,
-				fallback: () => {
-					// if fails, use old filereader
-					upload_with_filedata();
-				},
-				callback: (data) => {
-					args.file_url = data.file_url;
-					frappe.upload._upload_file(fileobj, args, opts);
-				},
-				on_progress: (percent_complete) => {
-					let increment = (flt(percent_complete) / frappe.upload.total_files);
-					frappe.show_progress(__('Uploading'),
-						start_complete + increment);
-				}
-			});
+			if (frappe.socketio.socket) {
+				frappe.socketio.uploader.start({
+					file: fileobj,
+					filename: args.filename,
+					is_private: args.is_private,
+					fallback: () => {
+						// if fails, use old filereader
+						upload_with_filedata();
+					},
+					callback: (data) => {
+						args.file_url = data.file_url;
+						frappe.upload._upload_file(fileobj, args, opts);
+					},
+					on_progress: (percent_complete) => {
+						let increment = (flt(percent_complete) / frappe.upload.total_files);
+						frappe.show_progress(__('Uploading'),
+							start_complete + increment);
+					}
+				});
+			}
 		}
 	},