diff --git a/custom_components/owncloud_backup/webdav_client.py b/custom_components/owncloud_backup/webdav_client.py
index ef0eb81..ae1299e 100644
--- a/custom_components/owncloud_backup/webdav_client.py
+++ b/custom_components/owncloud_backup/webdav_client.py
@@ -2,6 +2,7 @@ from __future__ import annotations
 
 import base64
 import logging
+import os
 import xml.etree.ElementTree as ET
 from collections.abc import AsyncIterator
 from datetime import datetime, timezone
@@ -9,6 +10,7 @@ from email.utils import parsedate_to_datetime
 from typing import Final
 from urllib.parse import quote, urljoin
 
+import aiohttp
 from aiohttp import ClientResponseError, ClientSession
 from yarl import URL
 
@@ -46,6 +48,11 @@ class WebDavClient:
         ]
         self._cached_root: str | None = None
 
+        # Non-restrictive client timeouts for potentially long WebDAV operations
+        self._timeout_long = aiohttp.ClientTimeout(
+            total=None, connect=60, sock_connect=60, sock_read=None
+        )
+
     def _auth_header(self) -> str:
         token = base64.b64encode(f"{self._username}:{self._password}".encode("utf-8")).decode("ascii")
         return f"Basic {token}"
@@ -82,6 +89,7 @@ class WebDavClient:
                         b'<d:propfind xmlns:d="DAV:"><d:prop><d:resourcetype/></d:prop></d:propfind>'
                     ),
                     raise_for_status=True,
+                    timeout=self._timeout_long,
                 ):
                     self._cached_root = root
                     return root
@@ -106,6 +114,7 @@ class WebDavClient:
                 base_folder,
                 headers=self._headers({"Depth": "0"}),
                 raise_for_status=True,
+                timeout=self._timeout_long,
             ):
                 return
         except ClientResponseError as err:
@@ -127,7 +136,11 @@ class WebDavClient:
         # exists?
         try:
             async with self._session.request(
-                "PROPFIND", url, headers=self._headers({"Depth": "0"}), raise_for_status=True
+                "PROPFIND",
+                url,
+                headers=self._headers({"Depth": "0"}),
+                raise_for_status=True,
+                timeout=self._timeout_long,
             ):
                 return
         except ClientResponseError as err:
@@ -135,7 +148,9 @@ class WebDavClient:
                 raise
 
         # create
-        async with self._session.request("MKCOL", url, headers=self._headers()) as resp:
+        async with self._session.request(
+            "MKCOL", url, headers=self._headers(), timeout=self._timeout_long
+        ) as resp:
             if resp.status in (201, 405):
                 return
             text = await resp.text()
@@ -154,6 +169,7 @@ class WebDavClient:
                 b'<d:propfind xmlns:d="DAV:"><d:prop><d:displayname/></d:prop></d:propfind>'
             ),
             raise_for_status=True,
+            timeout=self._timeout_long,
         ) as resp:
             body = await resp.text()
 
@@ -195,10 +211,42 @@ class WebDavClient:
     async def put_bytes(self, name: str, data: bytes) -> None:
         folder = await self._base_folder_url()
         url = self._file_url(folder, name)
-        async with self._session.put(url, data=data, headers=self._headers(), raise_for_status=True):
+        async with self._session.put(
+            url,
+            data=data,
+            headers=self._headers({"Content-Length": str(len(data))}),
+            raise_for_status=True,
+            timeout=self._timeout_long,
+        ):
             return
 
+    async def put_file(self, name: str, path: str, size: int) -> None:
+        """Upload a local file with an explicit Content-Length (non-chunked)."""
+        folder = await self._base_folder_url()
+        url = self._file_url(folder, name)
+
+        # Ensure correct size if caller passes 0/unknown
+        if size <= 0:
+            try:
+                size = os.path.getsize(path)
+            except OSError:
+                size = 0
+
+        headers = {"Content-Length": str(size)} if size > 0 else {}
+
+        # aiohttp will stream file content; with Content-Length set, proxies are usually happier.
+        with open(path, "rb") as f:
+            async with self._session.put(
+                url,
+                data=f,
+                headers=self._headers(headers),
+                raise_for_status=True,
+                timeout=self._timeout_long,
+            ):
+                return
+
     async def put_stream(self, name: str, stream: AsyncIterator[bytes]) -> None:
+        """Legacy method: chunked upload. Prefer put_file for better proxy compatibility."""
         folder = await self._base_folder_url()
         url = self._file_url(folder, name)
 
@@ -206,13 +254,19 @@ class WebDavClient:
             async for chunk in stream:
                 yield chunk
 
-        async with self._session.put(url, data=gen(), headers=self._headers(), raise_for_status=True):
+        async with self._session.put(
+            url,
+            data=gen(),
+            headers=self._headers(),
+            raise_for_status=True,
+            timeout=self._timeout_long,
+        ):
             return
 
     async def get_bytes(self, name: str) -> bytes:
         folder = await self._base_folder_url()
         url = self._file_url(folder, name)
-        async with self._session.get(url, headers=self._headers()) as resp:
+        async with self._session.get(url, headers=self._headers(), timeout=self._timeout_long) as resp:
             if resp.status == 404:
                 raise FileNotFoundError(name)
             resp.raise_for_status()
@@ -221,7 +275,7 @@ class WebDavClient:
     async def get_stream(self, name: str) -> AsyncIterator[bytes]:
         folder = await self._base_folder_url()
         url = self._file_url(folder, name)
-        resp = await self._session.get(url, headers=self._headers())
+        resp = await self._session.get(url, headers=self._headers(), timeout=self._timeout_long)
         if resp.status == 404:
             await resp.release()
             raise FileNotFoundError(name)
@@ -239,7 +293,7 @@ class WebDavClient:
     async def delete(self, name: str) -> None:
         folder = await self._base_folder_url()
         url = self._file_url(folder, name)
-        async with self._session.delete(url, headers=self._headers()) as resp:
+        async with self._session.delete(url, headers=self._headers(), timeout=self._timeout_long) as resp:
             if resp.status == 404:
                 raise FileNotFoundError(name)
             if resp.status in (200, 202, 204):
@@ -267,6 +321,7 @@ class WebDavClient:
             url,
             headers=self._headers({"Depth": "0", "Content-Type": "application/xml; charset=utf-8"}),
             data=body,
+            timeout=self._timeout_long,
         ) as resp:
             if resp.status == 404:
                 raise FileNotFoundError(name)