diff --git a/pentaract/src/errors.rs b/pentaract/src/errors.rs
index eaba1f6..18154ff 100644
--- a/pentaract/src/errors.rs
+++ b/pentaract/src/errors.rs
@@ -35,6 +35,8 @@ pub enum PentaractError {
     InvalidFolderName,
     #[error("You cannot manage access of yourself")]
     CannotManageAccessOfYourself,
+    #[error("Storage does not have workers")]
+    StorageDoesNotHaveWorkers,
     #[error("unknown error")]
     Unknown,
     #[error("{0} header is required")]
@@ -51,6 +53,7 @@ impl From<PentaractError> for (StatusCode, String) {
             | PentaractError::StorageChatIdConflict
             | PentaractError::StorageWorkerNameConflict
             | PentaractError::StorageWorkerTokenConflict
+            | PentaractError::StorageDoesNotHaveWorkers
             | PentaractError::CannotManageAccessOfYourself => (StatusCode::CONFLICT, e.to_string()),
             PentaractError::NotAuthenticated => (StatusCode::UNAUTHORIZED, e.to_string()),
             PentaractError::DoesNotExist(_) => (StatusCode::NOT_FOUND, e.to_string()),
diff --git a/pentaract/src/repositories/storage_workers.rs b/pentaract/src/repositories/storage_workers.rs
index c507a6b..df4625f 100644
--- a/pentaract/src/repositories/storage_workers.rs
+++ b/pentaract/src/repositories/storage_workers.rs
@@ -56,6 +56,18 @@ impl<'d> StorageWorkersRepository<'d> {
         Ok(sw)
     }
 
+    pub async fn storage_has_any(&self, storage_id: Uuid) -> PentaractResult<bool> {
+        let has_sws: (_,) = sqlx::query_as(&format!(
+            "SELECT COUNT(*) > 0 FROM {STORAGE_WORKERS_TABLE} WHERE storage_id = $1"
+        ))
+        .bind(storage_id)
+        .fetch_one(self.db)
+        .await
+        .map_err(|e| map_not_found(e, "storage_workers"))?;
+
+        Ok(has_sws.0)
+    }
+
     pub async fn list_by_user_id(&self, user_id: Uuid) -> PentaractResult<Vec<StorageWorker>> {
         sqlx::query_as(&format!(
             "SELECT * FROM {STORAGE_WORKERS_TABLE} WHERE user_id = $1"
diff --git a/pentaract/src/routers/storage_workers.rs b/pentaract/src/routers/storage_workers.rs
index fa92074..99b3ed3 100644
--- a/pentaract/src/routers/storage_workers.rs
+++ b/pentaract/src/routers/storage_workers.rs
@@ -1,8 +1,12 @@
 use std::sync::Arc;
 
 use axum::{
-    extract::State, http::StatusCode, middleware, response::IntoResponse, routing::get, Extension,
-    Json, Router,
+    extract::{Query, State},
+    http::StatusCode,
+    middleware,
+    response::{IntoResponse, Response},
+    routing::get,
+    Extension, Json, Router,
 };
 
 use crate::{
@@ -10,7 +14,9 @@ use crate::{
         jwt_manager::AuthUser,
         routing::{app_state::AppState, middlewares::auth::logged_in_required},
     },
-    schemas::storage_workers::InStorageWorkerSchema,
+    schemas::storage_workers::{
+        HasStorageWorkers, InStorageWorkerSchema, StorageWorkersStorageIDQuery,
+    },
     services::storage_workers::StorageWorkersService,
 };
 
@@ -20,6 +26,7 @@ impl StorageWorkersRouter {
     pub fn get_router(state: Arc<AppState>) -> Router {
         Router::new()
             .route("/", get(Self::list).post(Self::create))
+            .route("/has_workers", get(Self::has_storages_workers))
             .route_layer(middleware::from_fn_with_state(
                 state.clone(),
                 logged_in_required,
@@ -45,4 +52,15 @@ impl StorageWorkersRouter {
         let sws = StorageWorkersService::new(&state.db).list(&user).await?;
         Ok::<_, (StatusCode, String)>((StatusCode::OK, Json(sws)))
     }
+
+    pub async fn has_storages_workers(
+        State(state): State<Arc<AppState>>,
+        Extension(user): Extension<AuthUser>,
+        query: Query<StorageWorkersStorageIDQuery>,
+    ) -> Result<Response, (StatusCode, String)> {
+        let has = StorageWorkersService::new(&state.db)
+            .has_storage_workers(query.0.storage_id, &user)
+            .await?;
+        Ok(Json(HasStorageWorkers { has }).into_response())
+    }
 }
diff --git a/pentaract/src/schemas/storage_workers.rs b/pentaract/src/schemas/storage_workers.rs
index e817224..6caacc2 100644
--- a/pentaract/src/schemas/storage_workers.rs
+++ b/pentaract/src/schemas/storage_workers.rs
@@ -1,8 +1,19 @@
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
 
 #[derive(Deserialize)]
 pub struct InStorageWorkerSchema {
     pub name: String,
     pub token: String,
-    pub storage_id: Option<uuid::Uuid>,
+    pub storage_id: Option<Uuid>,
+}
+
+#[derive(Deserialize)]
+pub struct StorageWorkersStorageIDQuery {
+    pub storage_id: Uuid,
+}
+
+#[derive(Serialize)]
+pub struct HasStorageWorkers {
+    pub has: bool,
 }
diff --git a/pentaract/src/services/files.rs b/pentaract/src/services/files.rs
index fed935e..699894f 100644
--- a/pentaract/src/services/files.rs
+++ b/pentaract/src/services/files.rs
@@ -17,12 +17,15 @@ use crate::{
         access::AccessType,
         files::{FSElement, File, InFile},
     },
-    repositories::{access::AccessRepository, files::FilesRepository},
+    repositories::{
+        access::AccessRepository, files::FilesRepository, storage_workers::StorageWorkersRepository,
+    },
     schemas::files::{InFileSchema, InFolderSchema},
 };
 
 pub struct FilesService<'d> {
     repo: FilesRepository<'d>,
+    storage_workers_repo: StorageWorkersRepository<'d>,
     access_repo: AccessRepository<'d>,
     tx: ClientSender,
 }
@@ -30,10 +33,12 @@ pub struct FilesService<'d> {
 impl<'d> FilesService<'d> {
     pub fn new(db: &'d PgPool, tx: ClientSender) -> Self {
         let repo = FilesRepository::new(db);
+        let storage_workers_repo = StorageWorkersRepository::new(db);
         let access_repo = AccessRepository::new(db);
         Self {
             repo,
             access_repo,
+            storage_workers_repo,
             tx,
         }
     }
@@ -82,14 +87,17 @@ impl<'d> FilesService<'d> {
         )
         .await?;
 
-        // 1. path validation
+        // 1. check whether storage got workers
+        Self::check_storage_workers(&self, in_schema.storage_id).await?;
+
+        // 2. path validation
         if !Self::validate_filepath(&in_schema.path) {
             return Err(PentaractError::InvalidPath);
         }
 
         let in_file = InFile::new(in_schema.path, in_schema.size, in_schema.storage_id);
 
-        // 2. saving file to db
+        // 3. saving file to db
         let file = self.repo.create_file(in_file).await?;
 
         self._upload(file, in_schema.file, user).await
@@ -110,7 +118,10 @@ impl<'d> FilesService<'d> {
         )
         .await?;
 
-        // 1. saving file in db
+        // 1. check whether storage got workers
+        Self::check_storage_workers(&self, in_file.storage_id).await?;
+
+        // 2. saving file in db
         let file = self.repo.create_file_anyway(in_file).await?;
 
         self._upload(file, file_data, user).await
@@ -157,6 +168,18 @@ impl<'d> FilesService<'d> {
         Ok(())
     }
 
+    async fn check_storage_workers(&self, storage_id: Uuid) -> PentaractResult<()> {
+        if !self
+            .storage_workers_repo
+            .storage_has_any(storage_id)
+            .await?
+        {
+            Err(PentaractError::StorageDoesNotHaveWorkers)
+        } else {
+            Ok(())
+        }
+    }
+
     pub async fn download(
         &self,
         path: &str,
diff --git a/pentaract/src/services/storage_workers.rs b/pentaract/src/services/storage_workers.rs
index f6613d8..f87cdd0 100644
--- a/pentaract/src/services/storage_workers.rs
+++ b/pentaract/src/services/storage_workers.rs
@@ -1,21 +1,27 @@
 use sqlx::PgPool;
+use uuid::Uuid;
 
 use crate::{
-    common::jwt_manager::AuthUser,
+    common::{access::check_access, jwt_manager::AuthUser},
     errors::{PentaractError, PentaractResult},
-    models::storage_workers::{InStorageWorker, StorageWorker},
-    repositories::storage_workers::StorageWorkersRepository,
+    models::{
+        access::AccessType,
+        storage_workers::{InStorageWorker, StorageWorker},
+    },
+    repositories::{access::AccessRepository, storage_workers::StorageWorkersRepository},
     schemas::storage_workers::InStorageWorkerSchema,
 };
 
 pub struct StorageWorkersService<'d> {
     repo: StorageWorkersRepository<'d>,
+    access_repo: AccessRepository<'d>,
 }
 
 impl<'d> StorageWorkersService<'d> {
     pub fn new(db: &'d PgPool) -> Self {
         let repo = StorageWorkersRepository::new(db);
-        Self { repo }
+        let access_repo = AccessRepository::new(db);
+        Self { repo, access_repo }
     }
 
     pub async fn create(
@@ -45,4 +51,15 @@ impl<'d> StorageWorkersService<'d> {
     pub async fn list(&self, user: &AuthUser) -> PentaractResult<Vec<StorageWorker>> {
         self.repo.list_by_user_id(user.id).await
     }
+
+    pub async fn has_storage_workers(
+        &self,
+        storage_id: Uuid,
+        user: &AuthUser,
+    ) -> PentaractResult<bool> {
+        // 0. checking access
+        check_access(&self.access_repo, user.id, storage_id, &AccessType::R).await?;
+
+        self.repo.storage_has_any(storage_id).await
+    }
 }
diff --git a/ui/src/App.jsx b/ui/src/App.jsx
index 9e31ca9..fd4fc0d 100644
--- a/ui/src/App.jsx
+++ b/ui/src/App.jsx
@@ -11,6 +11,7 @@ import StorageWorkerCreateForm from './pages/StorageWorkers/StorageWorkerCreateF
 import Files from './pages/Files'
 import UploadFileTo from './pages/Files/UploadFileTo'
 import Register from './pages/Register'
+import NotFound from './pages/404'
 
 const theme = createTheme({
 	palette: {
@@ -41,6 +42,7 @@ const App = () => {
 						path="/storage_workers/register"
 						component={StorageWorkerCreateForm}
 					/>
+					<Route path="*404" component={NotFound} />
 				</Route>
 			</Routes>
 
diff --git a/ui/src/pages/404.jsx b/ui/src/pages/404.jsx
new file mode 100644
index 0000000..03ba594
--- /dev/null
+++ b/ui/src/pages/404.jsx
@@ -0,0 +1,21 @@
+import Typography from '@suid/material/Typography'
+import Box from '@suid/material/Box'
+
+const NotFound = () => {
+	return (
+		<Box
+			sx={{
+				display: 'flex',
+				alignItems: 'center',
+				justifyContent: 'center',
+				flexDirection: 'column',
+				mt: 16,
+			}}
+		>
+			<Typography variant="h1">404</Typography>
+			<Typography variant="h4">Not found</Typography>
+		</Box>
+	)
+}
+
+export default NotFound