diff --git a/.codex b/.codex
new file mode 100644
index 0000000..e69de29
diff --git a/.prettierrc b/.prettierrc
new file mode 100644
index 0000000..dc54f80
--- /dev/null
+++ b/.prettierrc
@@ -0,0 +1,5 @@
+{
+  "singleQuote": true,
+  "semi": false,
+  "trailingComma": "none"
+}
\ No newline at end of file
diff --git a/backend/controllers/ipController.js b/backend/controllers/ipController.js
index 7e405d8..04dfe86 100644
--- a/backend/controllers/ipController.js
+++ b/backend/controllers/ipController.js
@@ -35,24 +35,28 @@ exports.remove = async (req, res) => {
 };
 
 
+
 exports.update = async (req, res) => {
+  try {
+    const { ip, type, comment } = req.body
 
-    try{
-
-        const {ip, type, comment} = req.body;
-
-        await db.query(
-            "UPDATE resource_ips SET ip=?, type=?, comment=? WHERE id=?",
-            [ip, type, comment, req.params.id]
-        );
-
-        res.json({success:true});
-
-    }catch(e){
-
-        console.error("UPDATE IP error:", e);
-        res.status(500).json({error:"DB error"});
-
+    if (!ip) {
+      return res.status(400).json({ error: "IP darf nicht leer sein" })
     }
 
-};
+    await db.query(
+      "UPDATE resource_ips SET ip=?, type=?, comment=? WHERE id=?",
+      [ip, type, comment, req.params.id]
+    )
+
+    res.json({ success: true })
+
+  } catch (e) {
+    console.error("UPDATE IP error:", e)
+
+    res.status(500).json({
+      error: "IP konnte nicht gespeichert werden"
+    })
+  }
+}
+
diff --git a/backend/public/js/api.js b/backend/public/js/api.js
index 38956cd..29901dc 100644
--- a/backend/public/js/api.js
+++ b/backend/public/js/api.js
@@ -1,23 +1,23 @@
+const API = "/resman/api"
 
-const API="/resman/api";
+async function api(url, options = {}) {
+  const res = await fetch(url, options)
 
-async function api(url, options={}){
+  let data
 
-    const res = await fetch(url, options);
+  try {
+    data = await res.json()
+  } catch {
+    data = {}
+  }
 
-    if(!res.ok){
+  if (!res.ok) {
+    const msg = data.error || "Unbekannter Fehler"
 
-        let msg="API error";
+    showError(msg)
 
-        try{
-            const err=await res.json();
-            msg=err.error || msg;
-        }catch(e){}
-
-        alert("Fehler: "+msg);
-        throw new Error(msg);
-    }
-
-    return res.json();
-}
+    throw new Error(msg)
+  }
 
+  return data
+}
\ No newline at end of file
diff --git a/backend/public/js/main.js b/backend/public/js/main.js
index a6d3239..b517fc7 100644
--- a/backend/public/js/main.js
+++ b/backend/public/js/main.js
@@ -77,3 +77,25 @@ document.addEventListener("DOMContentLoaded", () => {
     }
 
 })
+
+function showError(msg) {
+
+  const div = document.createElement("div")
+
+  div.innerText = msg
+
+  div.style.position = "fixed"
+  div.style.bottom = "20px"
+  div.style.right = "20px"
+  div.style.background = "#dc2626"
+  div.style.color = "white"
+  div.style.padding = "10px 15px"
+  div.style.borderRadius = "6px"
+  div.style.zIndex = 9999
+
+  document.body.appendChild(div)
+
+  setTimeout(() => {
+    div.remove()
+  }, 3000)
+}
\ No newline at end of file
diff --git a/backend/public/js/resources.js b/backend/public/js/resources.js
index c154211..1a709a5 100644
--- a/backend/public/js/resources.js
+++ b/backend/public/js/resources.js
@@ -204,7 +204,9 @@ window.saveIP = async function(){
                     return
                 }
             }
-        }catch(e){}
+        }catch(e){
+            console.log("Save IP Fehler:", e)
+        }
 
         await api(API + "/resources/" + resourceId + "/ips", {
             method: "POST",
diff --git a/backend/server.js b/backend/server.js
index 87638e4..9023fcb 100644
--- a/backend/server.js
+++ b/backend/server.js
@@ -60,3 +60,11 @@ error: err.message || "Internal Server Error"
 app.listen(3000, () => {
   console.log("ResMan running on port 3000");
 });
+
+app.use((err, req, res, next) => {
+  console.error("GLOBAL ERROR:", err)
+
+  res.status(500).json({
+    error: "Interner Serverfehler"
+  })
+})
\ No newline at end of file
diff --git a/docker-compose.yml b/docker-compose.yml
index 3e28b3c..9c6b69a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,4 +1,4 @@
-version: "3.9"
+# version: "3.9"
 
 services:
   db: