diff --git a/client/src/Pages/Settings/index.tsx b/client/src/Pages/Settings/index.tsx
index 679d66126..e51255157 100644
--- a/client/src/Pages/Settings/index.tsx
+++ b/client/src/Pages/Settings/index.tsx
@@ -262,15 +262,7 @@ export const SettingsPage = () => {
 			if (value === undefined) {
 				(acc as any)[typedKey] = "";
 			} else if (typeof value === "object" && value !== null) {
-				// Handle nested objects like globalThresholds
-				// Convert 0 to "" for unsetting thresholds
-				(acc as any)[typedKey] = Object.entries(value).reduce(
-					(nested, [nestedKey, nestedValue]) => ({
-						...nested,
-						[nestedKey]: nestedValue === undefined ? "" : nestedValue,
-					}),
-					{}
-				);
+				(acc as any)[typedKey] = value;
 			} else {
 				(acc as any)[typedKey] = value;
 			}
diff --git a/server/src/controllers/settingsController.ts b/server/src/controllers/settingsController.ts
index d3caa0d8f..0fd82a8ac 100644
--- a/server/src/controllers/settingsController.ts
+++ b/server/src/controllers/settingsController.ts
@@ -2,14 +2,15 @@ import { Request, Response, NextFunction } from "express";
 import { updateAppSettingsBodyValidation } from "@/validation/settingsValidation.js";
 import { sendTestEmailBodyValidation } from "@/validation/notificationValidation.js";
 import { AppError } from "@/utils/AppError.js";
+import { IEmailService, ISettingsService } from "@/service/index.js";
 
 const SERVICE_NAME = "SettingsController";
 
 class SettingsController {
 	static SERVICE_NAME = SERVICE_NAME;
-	private settingsService: any;
-	private emailService: any;
-	constructor(settingsService: any, emailService: any) {
+	private settingsService: ISettingsService;
+	private emailService: IEmailService;
+	constructor(settingsService: ISettingsService, emailService: IEmailService) {
 		this.settingsService = settingsService;
 		this.emailService = emailService;
 	}
@@ -57,9 +58,9 @@ class SettingsController {
 
 	updateAppSettings = async (req: Request, res: Response, next: NextFunction) => {
 		try {
-			updateAppSettingsBodyValidation.parse(req.body);
+			const validatedBody = updateAppSettingsBodyValidation.parse(req.body);
 
-			const updatedSettings = await this.settingsService.updateDbSettings(req.body);
+			const updatedSettings = await this.settingsService.updateDbSettings(validatedBody);
 			const returnSettings = this.buildAppSettings(updatedSettings);
 			return res.status(200).json({
 				success: true,
@@ -95,6 +96,9 @@ class SettingsController {
 			const context = { testName: "Monitoring System" };
 
 			const html = await this.emailService.buildEmail("testEmailTemplate", context);
+			if (!html) {
+				throw new AppError({ message: "Failed to build email template.", status: 500 });
+			}
 			const messageId = await this.emailService.sendEmail(to, subject, html, {
 				systemEmailHost,
 				systemEmailPort,
diff --git a/server/src/service/system/settingsService.ts b/server/src/service/system/settingsService.ts
index ac4dfc425..10ac61725 100755
--- a/server/src/service/system/settingsService.ts
+++ b/server/src/service/system/settingsService.ts
@@ -19,6 +19,7 @@ export interface ISettingsService {
 	loadSettings(): EnvConfig;
 	getSettings(): EnvConfig;
 	getDBSettings(): Promise<Settings>;
+	updateDbSettings(newSettings: Partial<Settings>): Promise<Settings>;
 }
 
 export class SettingsService implements ISettingsService {
diff --git a/server/src/validation/settingsValidation.ts b/server/src/validation/settingsValidation.ts
index e7f0dc9b4..b9551dd4e 100644
--- a/server/src/validation/settingsValidation.ts
+++ b/server/src/validation/settingsValidation.ts
@@ -7,17 +7,17 @@ import { z } from "zod";
 
 export const updateAppSettingsBodyValidation = z
 	.object({
-		checkTTL: z.union([z.number().int().min(1).max(CHECK_TTL_SENTINEL), z.literal("")]).optional(),
-		systemEmailPort: z.union([z.number(), z.literal("")]).optional(),
-		pagespeedApiKey: z.union([z.string(), z.literal("")]).optional(),
-		language: z.union([z.string(), z.literal("")]).optional(),
-		timezone: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailHost: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailAddress: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailPassword: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailUser: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailConnectionHost: z.union([z.string(), z.literal("")]).optional(),
-		systemEmailTLSServername: z.union([z.string(), z.literal("")]).optional(),
+		checkTTL: z.number().int().min(1).max(CHECK_TTL_SENTINEL).optional(),
+		systemEmailPort: z.number().optional(),
+		pagespeedApiKey: z.string().optional(),
+		language: z.string().optional(),
+		timezone: z.string().optional(),
+		systemEmailHost: z.string().optional(),
+		systemEmailAddress: z.string().optional(),
+		systemEmailPassword: z.string().optional(),
+		systemEmailUser: z.string().optional(),
+		systemEmailConnectionHost: z.string().optional(),
+		systemEmailTLSServername: z.string().optional(),
 
 		showURL: z.boolean().optional(),
 		systemEmailSecure: z.boolean().optional(),
@@ -28,10 +28,10 @@ export const updateAppSettingsBodyValidation = z
 
 		globalThresholds: z
 			.object({
-				cpu: z.union([z.number().min(1).max(100), z.literal("")]).optional(),
-				memory: z.union([z.number().min(1).max(100), z.literal("")]).optional(),
-				disk: z.union([z.number().min(1).max(100), z.literal("")]).optional(),
-				temperature: z.union([z.number().min(1).max(150), z.literal("")]).optional(),
+				cpu: z.number().min(1).max(100).optional(),
+				memory: z.number().min(1).max(100).optional(),
+				disk: z.number().min(1).max(100).optional(),
+				temperature: z.number().min(1).max(150).optional(),
 			})
 			.optional(),
 	})