diff --git a/config/appsettings.json b/config/appsettings.json
index c1b551c20e..3cdae27a9e 100644
--- a/config/appsettings.json
+++ b/config/appsettings.json
@@ -65,249 +65,17 @@
     }
   },
   "files": {
-    "thirdparty": {
-      "enable": [
-        "box",
-        "dropboxv2",
-        "docusign",
-        "google",
-        "onedrive",
-        "nextcloud",
-        "owncloud",
-        "webdav",
-        "kdrive"
-      ]
-    },
+    "thirdparty": { "enable": ["box", "dropboxv2", "docusign", "google", "onedrive", "nextcloud", "owncloud", "webdav", "kdrive" ] },
     "docservice": {
-      "coauthor-docs": [
-		".csv",
-		".docm",
-		".docx",
-		".docxf",
-		".dotm",
-		".dotx",
-		".oform",
-		".potm",
-		".potx",
-		".ppsm",
-		".pptm",
-		".ppsx",
-		".pptx",
-		".txt",
-		".xlsm",
-		".xlsx",
-		".xltm",
-		".xltx"
-      ],
-      "commented-docs": [
-		".docm",
-		".docx",
-		".docxf",
-		".dotm",
-		".dotx",
-		".potm",
-		".potx",
-		".ppsm",
-		".pptm",
-		".ppsx",
-		".pptx",
-		".xlsm",
-		".xlsx",
-		".xltm",
-		".xltx"
-		],
-      "convert-docs": [
-		".doc",
-		".dot",
-		".dps",
-		".dpt",
-		".epub",
-		".et",
-		".ett",
-		".fb2",
-		".fodp",
-		".fods",
-		".fodt",
-		".htm",
-		".html",
-		".mht",
-		".mhtml",
-		".odp",
-		".ods",
-		".odt",
-		".otp",
-		".ots",
-		".ott",
-		".pot",
-		".pps",
-		".ppt",
-		".rtf",
-		".stw",
-		".sxc",
-		".sxi",
-		".sxw",
-		".wps",
-		".wpt",
-		".xls",
-		".xlsb",
-		".xlt",
-		".xml"
-      ],
-      "edited-docs": [
-		".csv",
-		".doc",
-		".docm",
-		".docx",
-		".docxf",
-		".dot",
-		".dotm",
-		".dotx",
-		".dps",
-		".dpt",
-		".epub",
-		".et",
-		".ett",
-		".fb2",
-		".fodp",
-		".fods",
-		".fodt",
-		".htm",
-		".html",
-		".mht",
-		".mhtml",
-		".odp",
-		".ods",
-		".odt",
-		".oform",
-		".otp",
-		".ots",
-		".ott",
-		".pdf",
-		".pot",
-		".potm",
-		".potx",
-		".pps",
-		".ppsm",
-		".ppsx",
-		".ppt",
-		".pptm",
-		".pptx",
-		".rtf",
-		".stw",
-		".sxc",
-		".sxi",
-		".sxw",
-		".txt",
-		".wps",
-		".wpt",
-		".xls",
-		".xlsb",
-		".xlsm",
-		".xlsx",
-		".xlt",
-		".xltm",
-		".xltx",
-		".xml"
-      ],
-      "encrypted-docs": 
-	  [
-		".docm",
-		".docx",
-		".docxf",
-		".dotm",
-		".dotx",
-		".oform",
-		".potm",
-		".potx",
-		".ppsm",
-		".pptm",
-		".ppsx",
-		".pptx",
-		".xlsm",
-		".xlsx",
-		".xltm",
-		".xltx",
-		".pdf"
-	  ],
+      "coauthor-docs": [ ".csv", ".docm", ".docx", ".docxf", ".dotm", ".dotx", ".oform", ".potm", ".potx", ".ppsm", ".pptm", ".ppsx", ".pptx", ".txt", ".xlsm", ".xlsx", ".xltm", ".xltx" ],
+      "commented-docs": [ ".docm", ".docx", ".docxf", ".dotm", ".dotx", ".potm", ".potx", ".ppsm", ".pptm", ".ppsx", ".pptx", ".xlsm", ".xlsx", ".xltm", ".xltx" ],
+      "convert-docs": [ ".doc", ".dot", ".dps", ".dpt", ".epub", ".et", ".ett", ".fb2", ".fodp", ".fods", ".fodt", ".htm", ".html", ".mht", ".mhtml", ".odp", ".ods", ".odt", ".otp", ".ots", ".ott", ".pot", ".pps", ".ppt", ".rtf", ".stw", ".sxc", ".sxi", ".sxw", ".wps", ".wpt", ".xls", ".xlsb", ".xlt", ".xml" ],
+      "edited-docs": [ ".csv", ".doc", ".docm", ".docx", ".docxf", ".dot", ".dotm", ".dotx", ".dps", ".dpt", ".epub", ".et", ".ett", ".fb2", ".fodp", ".fods", ".fodt", ".htm", ".html", ".mht", ".mhtml", ".odp", ".ods", ".odt", ".oform", ".otp", ".ots", ".ott", ".pdf", ".pot", ".potm", ".potx", ".pps", ".ppsm", ".ppsx", ".ppt", ".pptm", ".pptx", ".rtf", ".stw", ".sxc", ".sxi", ".sxw", ".txt", ".wps", ".wpt", ".xls", ".xlsb", ".xlsm", ".xlsx", ".xlt", ".xltm", ".xltx", ".xml" ],
+      "encrypted-docs": [ ".docm", ".docx", ".docxf", ".dotm", ".dotx", ".oform", ".potm", ".potx", ".ppsm", ".pptm", ".ppsx", ".pptx", ".xlsm", ".xlsx", ".xltm", ".xltx", ".pdf" ],
       "formfilling-docs": [".pdf"],
-      "customfilter-docs": 
-	  [
-		".xlsm",
-		".xlsx",
-		".xltm",
-		".xltx"
-	  ],
-      "reviewed-docs": 
-	  [
-		".docm",
-		".docx",
-		".docxf",
-		".dotm",
-		".dotx"
-	  ],
-      "viewed-docs": 
-	  [
-		".csv",
-		".djvu",
-		".doc",
-		".docm",
-		".docx",
-		".docxf",
-		".dot",
-		".dotm",
-		".dotx",
-		".dps",
-		".dpt",
-		".epub",
-		".et",
-		".ett",
-		".fb2",
-		".fodp",
-		".fods",
-		".fodt",
-		".gdoc",
-		".gsheet",
-		".gslides",
-		".htm",
-		".html",
-		".mht",
-		".mhtml",
-		".odp",
-		".ods",
-		".odt",
-		".oform",
-		".otp",
-		".ots",
-		".ott",
-		".oxps",
-		".pdf",
-		".pot",
-		".potm",
-		".potx",
-		".pps",
-		".ppsm",
-		".ppsx",
-		".ppt",
-		".pptm",
-		".pptx",
-		".rtf",
-		".stw",
-		".sxc",
-		".sxi",
-		".sxw",
-		".txt",
-		".wps",
-		".wpt",
-		".xls",
-		".xlsb",
-		".xlsm",
-		".xlsx",
-		".xlt",
-		".xltm",
-		".xltx",
-		".xml",
-		".xps"
-      ],
+      "customfilter-docs": [ ".xlsm", ".xlsx", ".xltm", ".xltx" ],
+      "reviewed-docs": [ ".docm", ".docx", ".docxf", ".dotm", ".dotx" ],
+      "viewed-docs": [ ".csv", ".djvu", ".doc", ".docm", ".docx", ".docxf", ".dot", ".dotm", ".dotx", ".dps", ".dpt", ".epub", ".et", ".ett", ".fb2", ".fodp", ".fods", ".fodt", ".gdoc", ".gsheet", ".gslides", ".htm", ".html", ".mht", ".mhtml", ".odp", ".ods", ".odt", ".oform", ".otp", ".ots", ".ott", ".oxps", ".pdf", ".pot", ".potm", ".potx", ".pps", ".ppsm", ".ppsx", ".ppt", ".pptm", ".pptx", ".rtf", ".stw", ".sxc", ".sxi", ".sxw", ".txt", ".wps", ".wpt", ".xls", ".xlsb", ".xlsm", ".xlsx", ".xlt", ".xltm", ".xltx", ".xml", ".xps" ],
       "secret": {
         "value": "secret",
         "header": "AuthorizationJwt"
@@ -326,33 +94,8 @@
       "chunk-size": 10485760,
       "url": "/"
     },
-    "viewed-images": [
-      ".svg",
-      ".bmp",
-      ".gif",
-      ".jpeg",
-      ".jpg",
-      ".png",
-      ".ico",
-      ".tif",
-      ".tiff",
-      ".webp"
-    ],
-    "viewed-media": [
-      ".aac",
-      ".flac",
-      ".m4a",
-      ".mp3",
-      ".oga",
-      ".ogg",
-      ".wav",
-      ".f4v",
-      ".m4v",
-      ".mov",
-      ".mp4",
-      ".ogv",
-      ".webm"
-    ],
+    "viewed-images": [ ".svg", ".bmp", ".gif", ".jpeg", ".jpg", ".png", ".ico", ".tif", ".tiff", ".webp" ],
+    "viewed-media": [ ".aac", ".flac", ".m4a", ".mp3", ".oga", ".ogg", ".wav", ".f4v", ".m4v", ".mov", ".mp4", ".ogv", ".webm" ],
     "index": [".pptx", ".xlsx", ".docx"],
     "oform": {
       "domain": "https://cmsoforms.teamlab.info",
@@ -472,47 +215,16 @@
   "thumbnail": {
     "maxDegreeOfParallelism": 1,
     "sizes": [
-      {
-        "height": 156,
-        "width": 216
-      },
-      {
-        "height": 156,
-        "width": 240
-      },
-      {
-        "height": 156,
-        "width": 264
-      },
-      {
-        "height": 156,
-        "width": 288
-      },
-      {
-        "height": 156,
-        "width": 312
-      },
-      {
-        "height": 156,
-        "width": 336
-      },
-      {
-        "height": 156,
-        "width": 360
-      },
-      {
-        "height": 156,
-        "width": 400
-      },
-      {
-        "height": 156,
-        "width": 440
-      },
-      {
-        "height": 720,
-        "width": 1280,
-        "resizeMode": "Max"
-      }
+      { "height": 156, "width": 216 },
+      { "height": 156, "width": 240 },
+      { "height": 156, "width": 264 },
+      { "height": 156, "width": 288 },
+	  { "height": 156, "width": 312 },
+	  { "height": 156, "width": 336 },
+	  { "height": 156, "width": 360 },
+	  { "height": 156, "width": 400 },
+	  { "height": 156, "width": 440 },
+	  { "height": 720, "width": 1280, "resizeMode": "Max" }
     ]
   },
   "csp": {
diff --git a/config/nginx/html/custom_401.html b/config/nginx/html/custom_401.html
new file mode 100644
index 0000000000..6941f0bab9
--- /dev/null
+++ b/config/nginx/html/custom_401.html
@@ -0,0 +1,88 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>401 Error Page</title>
+    <style>
+      body,
+      html {
+        height: 100%;
+        margin: 0px;
+        font-family: "Open Sans", Arial, sans-serif;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        background-color: #f0f0f0;
+      }
+
+      .error-container {
+        display: flex;
+        align-items: center;
+        flex-direction: column;
+        cursor: default;
+        width: auto;
+        height: 100vh;
+        overflow-x: hidden;
+        margin: 0px auto;
+        padding-top: 36px;
+        border: 0px;
+        box-sizing: border-box;
+        text-align: center;
+      }
+
+      .error-image {
+        max-width: 100%;
+        height: auto;
+        margin-bottom: 40px;
+      }
+
+      .error-header {
+        font-size: 23px;
+        line-height: 28px;
+        font-weight: 700;
+        color: #333333;
+        margin: 0px;
+        margin-bottom: 8px;
+      }
+
+      .error-text {
+        font-size: 12px;
+        line-height: 16px;
+        font-weight: 400;
+        color: #555f65;
+        margin: 0px;
+        margin-bottom: 24px;
+      }
+
+      @media (max-width: 600px) {
+        .error-container {
+          width: 343px;
+        }
+        .error-image {
+          width: 200px;
+          height: 200px;
+        }
+
+        .error-text {
+          max-width: 287px;
+          text-align: center;
+        }
+      }
+    </style>
+  </head>
+  <body>
+    <div class="error-container">
+      <img
+        src="/static/images/error401.svg"
+        alt="Error Character"
+        class="error-image"
+      />
+      <h1 class="error-header">401 Error!</h1>
+      <p class="error-text">
+        Unauthorized request. To access this file, you must enter a password or
+        be a registered user.
+      </p>
+    </div>
+  </body>
+</html>
diff --git a/config/nginx/html/custom_403.html b/config/nginx/html/custom_403.html
new file mode 100644
index 0000000000..984dfc844d
--- /dev/null
+++ b/config/nginx/html/custom_403.html
@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>403 Error Page</title>
+    <style>
+      body,
+      html {
+        height: 100%;
+        margin: 0px;
+        font-family: "Open Sans", Arial, sans-serif;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        background-color: #f0f0f0;
+      }
+
+      .error-container {
+        display: flex;
+        align-items: center;
+        flex-direction: column;
+        cursor: default;
+        width: auto;
+        height: 100vh;
+        overflow-x: hidden;
+        margin: 0px auto;
+        padding-top: 36px;
+        border: 0px;
+        box-sizing: border-box;
+        text-align: center;
+      }
+
+      .error-image {
+        max-width: 100%;
+        height: auto;
+        margin-bottom: 40px;
+      }
+
+      .error-header {
+        font-size: 23px;
+        line-height: 28px;
+        font-weight: 700;
+        color: #333333;
+        margin: 0px;
+        margin-bottom: 8px;
+      }
+
+      .error-text {
+        font-size: 12px;
+        line-height: 16px;
+        font-weight: 400;
+        color: #555f65;
+        margin: 0px;
+        margin-bottom: 24px;
+      }
+
+      @media (max-width: 600px) {
+        .error-container {
+          width: 343px;
+        }
+        .error-image {
+          width: 200px;
+          height: 200px;
+        }
+
+        .error-text {
+          max-width: 287px;
+          text-align: center;
+        }
+      }
+    </style>
+  </head>
+  <body>
+    <div class="error-container">
+      <img
+        src="/static/images/error403.svg"
+        alt="Error Character"
+        class="error-image"
+      />
+      <h1 class="error-header">403 Error!</h1>
+      <p class="error-text">
+        Forbidden. You don't have permissions to access the requested resource.
+      </p>
+    </div>
+  </body>
+</html>
diff --git a/config/nginx/html/custom_404.html b/config/nginx/html/custom_404.html
new file mode 100644
index 0000000000..9b7c22dd46
--- /dev/null
+++ b/config/nginx/html/custom_404.html
@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>404 Error Page</title>
+    <style>
+      body,
+      html {
+        height: 100%;
+        margin: 0px;
+        font-family: "Open Sans", Arial, sans-serif;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        background-color: #f0f0f0;
+      }
+
+      .error-container {
+        display: flex;
+        align-items: center;
+        flex-direction: column;
+        cursor: default;
+        width: auto;
+        height: 100vh;
+        overflow-x: hidden;
+        margin: 0px auto;
+        padding-top: 36px;
+        border: 0px;
+        box-sizing: border-box;
+        text-align: center;
+      }
+
+      .error-image {
+        max-width: 100%;
+        height: auto;
+        margin-bottom: 40px;
+      }
+
+      .error-header {
+        font-size: 23px;
+        line-height: 28px;
+        font-weight: 700;
+        color: #333333;
+        margin: 0px;
+        margin-bottom: 8px;
+      }
+
+      .error-text {
+        font-size: 12px;
+        line-height: 16px;
+        font-weight: 400;
+        color: #555f65;
+        margin: 0px;
+        margin-bottom: 24px;
+      }
+
+      @media (max-width: 600px) {
+        .error-container {
+          width: 343px;
+        }
+        .error-image {
+          width: 200px;
+          height: 200px;
+        }
+
+        .error-text {
+          max-width: 287px;
+          text-align: center;
+        }
+      }
+    </style>
+  </head>
+  <body>
+    <div class="error-container">
+      <img
+        src="/static/images/error404.svg"
+        alt="Error Character"
+        class="error-image"
+      />
+      <h1 class="error-header">404 Error!</h1>
+      <p class="error-text">
+        Page not found. The server cannot find the requested resource.
+      </p>
+    </div>
+  </body>
+</html>
diff --git a/config/nginx/html/custom_50x.html b/config/nginx/html/custom_50x.html
new file mode 100644
index 0000000000..be489db1cd
--- /dev/null
+++ b/config/nginx/html/custom_50x.html
@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>500 Error Page</title>
+    <style>
+      body,
+      html {
+        height: 100%;
+        margin: 0px;
+        font-family: "Open Sans", Arial, sans-serif;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        background-color: #f0f0f0;
+      }
+
+      .error-container {
+        display: flex;
+        align-items: center;
+        flex-direction: column;
+        cursor: default;
+        width: auto;
+        height: 100vh;
+        overflow-x: hidden;
+        margin: 0px auto;
+        padding-top: 36px;
+        border: 0px;
+        box-sizing: border-box;
+        text-align: center;
+      }
+
+      .error-image {
+        max-width: 100%;
+        height: auto;
+        margin-bottom: 40px;
+      }
+
+      .error-header {
+        font-size: 23px;
+        line-height: 28px;
+        font-weight: 700;
+        color: #333333;
+        margin: 0px;
+        margin-bottom: 8px;
+      }
+
+      .error-text {
+        font-size: 12px;
+        line-height: 16px;
+        font-weight: 400;
+        color: #555f65;
+        margin: 0px;
+        margin-bottom: 24px;
+      }
+
+      @media (max-width: 600px) {
+        .error-container {
+          width: 343px;
+        }
+        .error-image {
+          width: 200px;
+          height: 200px;
+        }
+
+        .error-text {
+          max-width: 287px;
+          text-align: center;
+        }
+      }
+    </style>
+  </head>
+  <body>
+    <div class="error-container">
+      <img
+        src="/static/images/error500.svg"
+        alt="Error Character"
+        class="error-image"
+      />
+      <h1 class="error-header">500 Error!</h1>
+      <p class="error-text">
+        The server is currently unable to handle this request.
+      </p>
+    </div>
+  </body>
+</html>
diff --git a/config/nginx/onlyoffice.conf b/config/nginx/onlyoffice.conf
index 2df33d5618..f4a1a70966 100644
--- a/config/nginx/onlyoffice.conf
+++ b/config/nginx/onlyoffice.conf
@@ -366,4 +366,28 @@ server {
 		rewrite /healthchecks/(.*)$ /$1 break;
 		proxy_pass http://127.0.0.1:5033;
     }
+
+	error_page 401 /custom_401.html;
+    location = /custom_401.html {
+        root /etc/nginx/html;
+        internal;
+    }
+
+	error_page 403 /custom_403.html;
+    location = /custom_403.html {
+        root /etc/nginx/html;
+        internal;
+    }
+
+	error_page 404 /custom_404.html;
+    location = /custom_404.html {
+        root /etc/nginx/html;
+        internal;
+    }
+
+    error_page 500 502 503 504 /custom_50x.html;
+    location = /custom_50x.html {
+        root /etc/nginx/html;
+        internal;
+    }
 }
diff --git a/install/docker/Dockerfile.runtime b/install/docker/Dockerfile.runtime
index 82d173e402..1a8a023bb2 100644
--- a/install/docker/Dockerfile.runtime
+++ b/install/docker/Dockerfile.runtime
@@ -15,6 +15,7 @@ RUN find config/ -maxdepth 1 -name "*.json" | grep -v test | grep -v dev | xargs
     tar -C "/app/onlyoffice/" -xvf config.tar && \
     cp config/*.config /app/onlyoffice/config/ && \
     mkdir -p /etc/nginx/conf.d && cp -f config/nginx/onlyoffice*.conf /etc/nginx/conf.d/ && \
+    mkdir -p /etc/nginx/html && cp -f config/nginx/html/* /etc/nginx/html/ && \
     mkdir -p /etc/nginx/includes/ && cp -f config/nginx/includes/onlyoffice*.conf /etc/nginx/includes/ && \
     sed -i "s/\"number\".*,/\"number\": \"${PRODUCT_VERSION}.${BUILD_NUMBER}\",/g" /app/onlyoffice/config/appsettings.json && \
     sed -e 's/#//' -i /etc/nginx/conf.d/onlyoffice.conf
@@ -92,6 +93,7 @@ RUN apt-get -y update && \
 
 # copy static services files and config values 
 COPY --from=base /etc/nginx/conf.d /etc/nginx/conf.d
+COPY --from=base /etc/nginx/html /etc/nginx/html
 
 COPY /buildtools/install/docker/config/nginx/docker-entrypoint.sh /docker-entrypoint.sh
 COPY /buildtools/install/docker/config/nginx/docker-entrypoint.d /docker-entrypoint.d