diff --git a/src/app/course/[courseName]/modules/NewItemForm.tsx b/src/app/course/[courseName]/modules/NewItemForm.tsx
index b4d0d64..abbe5de 100644
--- a/src/app/course/[courseName]/modules/NewItemForm.tsx
+++ b/src/app/course/[courseName]/modules/NewItemForm.tsx
@@ -17,6 +17,7 @@ import {
   getDateFromStringOrThrow,
 } from "@/features/local/utils/timeUtils";
 import { useCreateAssignmentMutation } from "@/features/local/assignments/assignmentHooks";
+import { validateFileName } from "@/services/fileNameValidation";
 
 export default function NewItemForm({
   moduleName: defaultModuleName,
@@ -41,20 +42,6 @@ export default function NewItemForm({
   const [name, setName] = useState("");
   const [nameError, setNameError] = useState("");
 
-  const validateFileName = (fileName: string): string => {
-    // Check for invalid file system characters
-    const invalidChars = [":", "/", "\\", "*", '"', "<", ">", "|"];
-
-    for (const char of fileName) {
-      if (invalidChars.includes(char)) {
-        return `Name contains invalid character: "${char}". Please avoid: ${invalidChars.join(
-          " "
-        )}`;
-      }
-    }
-    return "";
-  };
-
   const handleNameChange = (newName: string) => {
     setName(newName);
     const error = validateFileName(newName);
diff --git a/src/features/local/assignments/assignmentRouter.ts b/src/features/local/assignments/assignmentRouter.ts
index 8bdf173..5df4124 100644
--- a/src/features/local/assignments/assignmentRouter.ts
+++ b/src/features/local/assignments/assignmentRouter.ts
@@ -10,6 +10,7 @@ import { getCoursePathByName } from "../globalSettings/globalSettingsFileStorage
 import { promises as fs } from "fs";
 import { courseItemFileStorageService } from "../course/courseItemFileStorageService";
 import { assignmentMarkdownSerializer } from "./models/utils/assignmentMarkdownSerializer";
+import { assertValidFileName } from "@/services/fileNameValidation";
 
 export const assignmentRouter = router({
   getAssignment: publicProcedure
@@ -133,16 +134,7 @@ export async function updateOrCreateAssignmentFile({
   assignmentName: string;
   assignment: LocalAssignment;
 }) {
-  const illegalCharacters = ["<", ">", ":", '"', "/", "\\", "|", "?", "*"];
-  const foundIllegalCharacters = illegalCharacters.filter((char) =>
-    assignmentName.includes(char)
-  );
-  if (foundIllegalCharacters.length > 0) {
-    throw new Error(
-      `"${assignmentName}" cannot contain the following characters: ${foundIllegalCharacters.join(
-        " "
-      )}`
-    );
+  assertValidFileName(assignmentName);
   }
 
   const courseDirectory = await getCoursePathByName(courseName);
diff --git a/src/features/local/pages/pageRouter.ts b/src/features/local/pages/pageRouter.ts
index 0290a01..a97d968 100644
--- a/src/features/local/pages/pageRouter.ts
+++ b/src/features/local/pages/pageRouter.ts
@@ -1,11 +1,16 @@
 import publicProcedure from "../../../services/serverFunctions/publicProcedure";
 import { z } from "zod";
 import { router } from "../../../services/serverFunctions/trpcSetup";
-import { LocalCoursePage, localPageMarkdownUtils, zodLocalCoursePage } from "@/features/local/pages/localCoursePageModels";
+import {
+  LocalCoursePage,
+  localPageMarkdownUtils,
+  zodLocalCoursePage,
+} from "@/features/local/pages/localCoursePageModels";
 import { courseItemFileStorageService } from "../course/courseItemFileStorageService";
 import { promises as fs } from "fs";
 import path from "path";
 import { getCoursePathByName } from "../globalSettings/globalSettingsFileStorageService";
+import { assertValidFileName } from "@/services/fileNameValidation";
 
 export const pageRouter = router({
   getPage: publicProcedure
@@ -115,31 +120,32 @@ export const pageRouter = router({
 });
 
 export async function updatePageFile({
-    courseName,
+  courseName,
+  moduleName,
+  pageName,
+  page,
+}: {
+  courseName: string;
+  moduleName: string;
+  pageName: string;
+  page: LocalCoursePage;
+}) {
+  assertValidFileName(pageName);
+  const courseDirectory = await getCoursePathByName(courseName);
+  const folder = path.join(courseDirectory, moduleName, "pages");
+  await fs.mkdir(folder, { recursive: true });
+
+  const filePath = path.join(
+    courseDirectory,
     moduleName,
-    pageName,
-    page,
-  }: {
-    courseName: string;
-    moduleName: string;
-    pageName: string;
-    page: LocalCoursePage;
-  }) {
-    const courseDirectory = await getCoursePathByName(courseName);
-    const folder = path.join(courseDirectory, moduleName, "pages");
-    await fs.mkdir(folder, { recursive: true });
+    "pages",
+    pageName + ".md"
+  );
 
-    const filePath = path.join(
-      courseDirectory,
-      moduleName,
-      "pages",
-      pageName + ".md"
-    );
-
-    const pageMarkdown = localPageMarkdownUtils.toMarkdown(page);
-    console.log(`Saving page ${filePath}`);
-    await fs.writeFile(filePath, pageMarkdown);
-  }
+  const pageMarkdown = localPageMarkdownUtils.toMarkdown(page);
+  console.log(`Saving page ${filePath}`);
+  await fs.writeFile(filePath, pageMarkdown);
+}
 async function deletePageFile({
   courseName,
   moduleName,
diff --git a/src/features/local/quizzes/quizRouter.ts b/src/features/local/quizzes/quizRouter.ts
index 0c8d956..c82b33a 100644
--- a/src/features/local/quizzes/quizRouter.ts
+++ b/src/features/local/quizzes/quizRouter.ts
@@ -10,6 +10,7 @@ import path from "path";
 import { promises as fs } from "fs";
 import { quizMarkdownUtils } from "./models/utils/quizMarkdownUtils";
 import { courseItemFileStorageService } from "../course/courseItemFileStorageService";
+import { assertValidFileName } from "@/services/fileNameValidation";
 
 export const quizRouter = router({
   getQuiz: publicProcedure
@@ -149,6 +150,7 @@ export async function updateQuizFile({
   quizName: string;
   quiz: LocalQuiz;
 }) {
+  assertValidFileName(quizName);
   const courseDirectory = await getCoursePathByName(courseName);
   const folder = path.join(courseDirectory, moduleName, "quizzes");
   await fs.mkdir(folder, { recursive: true });
diff --git a/src/services/fileNameValidation.ts b/src/services/fileNameValidation.ts
new file mode 100644
index 0000000..b3068a5
--- /dev/null
+++ b/src/services/fileNameValidation.ts
@@ -0,0 +1,28 @@
+export function validateFileName(fileName: string): string {
+  if (!fileName || fileName.trim() === "") {
+    return "Name cannot be empty";
+  }
+
+  const invalidChars = [":", "/", "\\", "*", "?", '"', "<", ">", "|"];
+
+  for (const char of fileName) {
+    if (invalidChars.includes(char)) {
+      return `Name contains invalid character: "${char}". Please avoid: ${invalidChars.join(
+        " "
+      )}`;
+    }
+  }
+
+  if (fileName !== fileName.trimEnd()) {
+    return "Name cannot end with whitespace";
+  }
+
+  return "";
+}
+
+export function assertValidFileName(fileName: string): void {
+  const error = validateFileName(fileName);
+  if (error) {
+    throw new Error(error);
+  }
+}