diff --git a/control/frontend/src/lib/ts/api_handler.ts b/control/frontend/src/lib/ts/api_handler.ts
index f4a6205..72368e1 100755
--- a/control/frontend/src/lib/ts/api_handler.ts
+++ b/control/frontend/src/lib/ts/api_handler.ts
@@ -84,9 +84,10 @@ export async function get_file_data(
     `;
 	const raw_response = await run_shell_command(ip, command);
 	if (!raw_response.ok || !raw_response.json) return null;
+	if (!raw_response.ok) return null;
+	if (handle_shell_error(ip, raw_response, command, true)) return null;
+
 	const json_response = raw_response.json as ShellCommandResponse;
-	if (json_response.exitCode === 0 && json_response.stdout.trim() === '') return [];
-	if (handle_shell_error(ip, json_response, command, true)) return null;
 	if (json_response.stdout.trim() === '') return null;
 
 	const response: FileInfo[] = json_response.stdout
@@ -116,11 +117,10 @@ export async function get_file_data(
 export async function get_file_tree_data(ip: string, path: string): Promise<TreeElement[] | null> {
 	const command = `cd ".${path}" && tree -Js`;
 	const raw_response = await run_shell_command(ip, command);
+	if (!raw_response.ok) return null;
+	if (handle_shell_error(ip, raw_response, command, true)) return null;
 
-	if (!raw_response.ok || !raw_response.json) return null;
 	const json_response = raw_response.json as ShellCommandResponse;
-	if (handle_shell_error(ip, json_response, command, true)) return null;
-
 	const tree_element: TreeElement | null = JSON.parse(json_response.stdout.trim())[0] || null;
 
 	return tree_element?.contents || null;
@@ -130,9 +130,8 @@ export async function create_path(ip: string, path: string): Promise<void> {
 	const command = `mkdir -p ".${path}"`;
 
 	const raw_response = await run_shell_command(ip, command);
-	if (!raw_response.ok || !raw_response.json) return;
-	const json_response = raw_response.json as ShellCommandResponse;
-	handle_shell_error(ip, json_response, command, true);
+	if (!raw_response.ok) return;
+	handle_shell_error(ip, raw_response, command, true);
 }
 
 export async function rename_file(
@@ -144,9 +143,8 @@ export async function rename_file(
 	const command: string = `cd ".${path}" && mv "${old_file_name}" "${new_file_name}"`;
 
 	const raw_response = await run_shell_command(ip, command);
-	if (!raw_response.ok || !raw_response.json) return;
-	const json_response = raw_response.json as ShellCommandResponse;
-	handle_shell_error(ip, json_response, command, true);
+	if (!raw_response.ok) return;
+	handle_shell_error(ip, raw_response, command, true);
 }
 
 export async function delete_files(
@@ -159,9 +157,8 @@ export async function delete_files(
 		command += ` && rm -r "${file_name}"`;
 	}
 	const raw_response = await run_shell_command(ip, command);
-	if (!raw_response.ok || !raw_response.json) return;
-	const json_response = raw_response.json as ShellCommandResponse;
-	handle_shell_error(ip, json_response, command, true);
+	if (!raw_response.ok) return;
+	handle_shell_error(ip, raw_response, command, true);
 }
 
 export async function show_blackscreen(ip: string): Promise<void> {
@@ -288,11 +285,21 @@ async function request(
 
 function handle_shell_error(
 	ip: string,
-	shell_response: ShellCommandResponse,
+	response: RequestResponse,
 	shell_command: string,
-	command_includs_cd: boolean
+	command_includs_cd: boolean,
+	response_type: 'json' | 'blob' = 'json'
 ): boolean {
-	if (shell_response.exitCode !== 0) {
+	if (
+		(response_type === 'json' && !response.json) ||
+		(response_type === 'blob' && !response.blob)
+	) {
+		const error_string = `Did not receive ${response_type}: ${JSON.stringify(response)}`;
+		console.error(error_string);
+		notifications.push('error', `Fehler in API-Shell`, `${ip}\n${shell_command}\n${error_string}`);
+		return true;
+	} else if (response.json && response.json.exitCode !== 0) {
+		const shell_response = response.json as ShellCommandResponse;
 		if (
 			command_includs_cd &&
 			shell_response.stderr &&