diff --git a/.eslintignore b/.eslintignore
index 7e298e2c8..af0a6c8bc 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -1176,6 +1176,9 @@ packages/lib/models/utils/paginationToSql.js.map
 packages/lib/models/utils/types.d.ts
 packages/lib/models/utils/types.js
 packages/lib/models/utils/types.js.map
+packages/lib/net-utils.d.ts
+packages/lib/net-utils.js
+packages/lib/net-utils.js.map
 packages/lib/ntp.d.ts
 packages/lib/ntp.js
 packages/lib/ntp.js.map
diff --git a/.gitignore b/.gitignore
index 25f7354ce..5e4f054e9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1159,6 +1159,9 @@ packages/lib/models/utils/paginationToSql.js.map
 packages/lib/models/utils/types.d.ts
 packages/lib/models/utils/types.js
 packages/lib/models/utils/types.js.map
+packages/lib/net-utils.d.ts
+packages/lib/net-utils.js
+packages/lib/net-utils.js.map
 packages/lib/ntp.d.ts
 packages/lib/ntp.js
 packages/lib/ntp.js.map
diff --git a/packages/app-cli/app/ResourceServer.js b/packages/app-cli/app/ResourceServer.js
index 90eb7ad11..ac6e2ed19 100644
--- a/packages/app-cli/app/ResourceServer.js
+++ b/packages/app-cli/app/ResourceServer.js
@@ -1,5 +1,5 @@
 const Logger = require('@joplin/lib/Logger').default;
-const { netUtils } = require('@joplin/lib/net-utils.js');
+const { findAvailablePort } = require('@joplin/lib/net-utils');
 
 const http = require('http');
 const urlParser = require('url');
@@ -36,7 +36,7 @@ class ResourceServer {
 	}
 
 	async start() {
-		this.port_ = await netUtils.findAvailablePort([9167, 9267, 8167, 8267]);
+		this.port_ = await findAvailablePort([9167, 9267, 8167, 8267]);
 		if (!this.port_) {
 			this.logger().error('Could not find available port to start resource server. Please report the error at https://github.com/laurent22/joplin');
 			return;
diff --git a/packages/lib/JoplinServerApi.ts b/packages/lib/JoplinServerApi.ts
index 18a5f7974..05cc50568 100644
--- a/packages/lib/JoplinServerApi.ts
+++ b/packages/lib/JoplinServerApi.ts
@@ -5,6 +5,7 @@ import JoplinError from './JoplinError';
 import { Env } from './models/Setting';
 import Logger from './Logger';
 import personalizedUserContentBaseUrl from './services/joplinServer/personalizedUserContentBaseUrl';
+import { getHttpStatusMessage } from './net-utils';
 const { stringify } = require('query-string');
 
 const logger = Logger.create('JoplinServerApi');
@@ -245,7 +246,7 @@ export default class JoplinServerApi {
 				//         <hr><center>nginx/1.18.0 (Ubuntu)</center>
 				//     </body>
 				// </html>
-				throw newError(`Unknown error: ${shortResponseText()}`, response.status);
+				throw newError(`Error ${response.status} ${getHttpStatusMessage(response.status)}: ${shortResponseText()}`, response.status);
 			}
 
 			if (options.responseFormat === 'text') return responseText;
diff --git a/packages/lib/net-utils.js b/packages/lib/net-utils.js
deleted file mode 100644
index d36def19a..000000000
--- a/packages/lib/net-utils.js
+++ /dev/null
@@ -1,40 +0,0 @@
-const shim = require('./shim').default;
-
-const netUtils = {};
-
-netUtils.ip = async () => {
-	const response = await shim.fetch('https://api.ipify.org/?format=json');
-	if (!response.ok) {
-		throw new Error(`Could not retrieve IP: ${await response.text()}`);
-	}
-
-	const ip = await response.json();
-	return ip.ip;
-};
-
-netUtils.findAvailablePort = async (possiblePorts, extraRandomPortsToTry = 20) => {
-	const tcpPortUsed = require('tcp-port-used');
-
-	for (let i = 0; i < extraRandomPortsToTry; i++) {
-		possiblePorts.push(Math.floor(8000 + Math.random() * 2000));
-	}
-
-	let port = null;
-	for (let i = 0; i < possiblePorts.length; i++) {
-		const inUse = await tcpPortUsed.check(possiblePorts[i]);
-		if (!inUse) {
-			port = possiblePorts[i];
-			break;
-		}
-	}
-	return port;
-};
-
-netUtils.mimeTypeFromHeaders = headers => {
-	if (!headers || !headers['content-type']) return null;
-
-	const splitted = headers['content-type'].split(';');
-	return splitted[0].trim().toLowerCase();
-};
-
-module.exports = { netUtils };
diff --git a/packages/lib/net-utils.ts b/packages/lib/net-utils.ts
new file mode 100644
index 000000000..4a32e1f47
--- /dev/null
+++ b/packages/lib/net-utils.ts
@@ -0,0 +1,112 @@
+import shim from './shim';
+
+export async function ip() {
+	const response = await shim.fetch('https://api.ipify.org/?format=json');
+	if (!response.ok) {
+		throw new Error(`Could not retrieve IP: ${await response.text()}`);
+	}
+
+	const ip = await response.json();
+	return ip.ip;
+}
+
+export async function findAvailablePort(possiblePorts: number[], extraRandomPortsToTry = 20) {
+	const tcpPortUsed = require('tcp-port-used');
+
+	for (let i = 0; i < extraRandomPortsToTry; i++) {
+		possiblePorts.push(Math.floor(8000 + Math.random() * 2000));
+	}
+
+	let port = null;
+	for (let i = 0; i < possiblePorts.length; i++) {
+		const inUse = await tcpPortUsed.check(possiblePorts[i]);
+		if (!inUse) {
+			port = possiblePorts[i];
+			break;
+		}
+	}
+	return port;
+}
+
+export async function mimeTypeFromHeaders(headers: Record<string, any>) {
+	if (!headers || !headers['content-type']) return null;
+
+	const splitted = headers['content-type'].split(';');
+	return splitted[0].trim().toLowerCase();
+}
+
+
+const httpStatusCodes_: Record<number, string> = {
+	100: 'Continue',
+	101: 'Switching Protocols',
+	102: 'Processing',
+	103: 'Early Hints',
+	200: 'OK',
+	201: 'Created',
+	202: 'Accepted',
+	203: 'Non-Authoritative Information',
+	204: 'No Content',
+	205: 'Reset Content',
+	206: 'Partial Content',
+	207: 'Multi-Status',
+	208: 'Already Reported',
+	226: 'IM Used',
+	300: 'Multiple Choices',
+	301: 'Moved Permanently',
+	302: 'Found',
+	303: 'See Other',
+	304: 'Not Modified',
+	305: 'Use Proxy',
+	307: 'Temporary Redirect',
+	308: 'Permanent Redirect',
+	400: 'Bad Request',
+	401: 'Unauthorized',
+	402: 'Payment Required',
+	403: 'Forbidden',
+	404: 'Not Found',
+	405: 'Method Not Allowed',
+	406: 'Not Acceptable',
+	407: 'Proxy Authentication Required',
+	408: 'Request Timeout',
+	409: 'Conflict',
+	410: 'Gone',
+	411: 'Length Required',
+	412: 'Precondition Failed',
+	413: 'Payload Too Large',
+	414: 'URI Too Long',
+	415: 'Unsupported Media Type',
+	416: 'Range Not Satisfiable',
+	417: 'Expectation Failed',
+	418: 'I\'m a Teapot',
+	421: 'Misdirected Request',
+	422: 'Unprocessable Entity',
+	423: 'Locked',
+	424: 'Failed Dependency',
+	425: 'Too Early',
+	426: 'Upgrade Required',
+	428: 'Precondition Required',
+	429: 'Too Many Requests',
+	431: 'Request Header Fields Too Large',
+	451: 'Unavailable For Legal Reasons',
+	500: 'Internal Server Error',
+	501: 'Not Implemented',
+	502: 'Bad Gateway',
+	503: 'Service Unavailable',
+	504: 'Gateway Timeout',
+	505: 'HTTP Version Not Supported',
+	506: 'Variant Also Negotiates',
+	507: 'Insufficient Storage',
+	508: 'Loop Detected',
+	509: 'Bandwidth Limit Exceeded',
+	510: 'Not Extended',
+	511: 'Network Authentication Required',
+};
+
+export function getHttpStatusMessage(statusCode: number): string {
+	const msg = httpStatusCodes_[statusCode];
+
+	// We don't throw an exception since a server can send any arbitrary error code
+	if (!msg) return 'Unknown status code';
+
+	return msg;
+}
diff --git a/packages/lib/onedrive-api-node-utils.js b/packages/lib/onedrive-api-node-utils.js
index c85f263fb..588c18218 100644
--- a/packages/lib/onedrive-api-node-utils.js
+++ b/packages/lib/onedrive-api-node-utils.js
@@ -1,5 +1,5 @@
 const { _ } = require('./locale');
-const { netUtils } = require('./net-utils.js');
+const { findAvailablePort } = require('./net-utils');
 const shim = require('./shim').default;
 
 const http = require('http');
@@ -42,7 +42,7 @@ class OneDriveApiNodeUtils {
 
 		this.api().setAuth(null);
 
-		const port = await netUtils.findAvailablePort(this.possibleOAuthDancePorts(), 0);
+		const port = await findAvailablePort(this.possibleOAuthDancePorts(), 0);
 		if (!port) throw new Error(_('All potential ports are in use - please report the issue at %s', 'https://github.com/laurent22/joplin'));
 
 		const authCodeUrl = this.api().authCodeUrl(`http://localhost:${port}`);
diff --git a/packages/lib/services/rest/routes/notes.ts b/packages/lib/services/rest/routes/notes.ts
index 48d929ebe..506e6923e 100644
--- a/packages/lib/services/rest/routes/notes.ts
+++ b/packages/lib/services/rest/routes/notes.ts
@@ -23,7 +23,7 @@ const md5 = require('md5');
 import HtmlToMd from '../../../HtmlToMd';
 const urlUtils = require('../../../urlUtils.js');
 const ArrayUtils = require('../../../ArrayUtils.js');
-const { netUtils } = require('../../../net-utils');
+const { mimeTypeFromHeaders } = require('../../../net-utils');
 const { fileExtension, safeFileExtension, safeFilename, filename } = require('../../../path-utils');
 const uri2path = require('file-uri-to-path');
 const { MarkupToHtml } = require('@joplin/renderer');
@@ -144,7 +144,7 @@ async function buildNoteStyleSheet(stylesheets: any[]) {
 }
 
 async function tryToGuessImageExtFromMimeType(response: any, imagePath: string) {
-	const mimeType = netUtils.mimeTypeFromHeaders(response.headers);
+	const mimeType = mimeTypeFromHeaders(response.headers);
 	if (!mimeType) return imagePath;
 
 	const newExt = mimeUtils.toFileExtension(mimeType);
diff --git a/packages/tools/fetchPatreonPosts.js b/packages/tools/fetchPatreonPosts.js
index 3df05cbcc..dc2fba5b5 100644
--- a/packages/tools/fetchPatreonPosts.js
+++ b/packages/tools/fetchPatreonPosts.js
@@ -8,7 +8,7 @@ const HtmlToMd = require('@joplin/lib/HtmlToMd').default;
 const { dirname, filename, basename } = require('@joplin/lib/path-utils');
 const markdownUtils = require('@joplin/lib/markdownUtils').default;
 const mimeUtils = require('@joplin/lib/mime-utils.js').mime;
-const { netUtils } = require('@joplin/lib/net-utils');
+const { mimeTypeFromHeaders } = require('@joplin/lib/net-utils');
 const shim = require('@joplin/lib/shim').default;
 const moment = require('moment');
 const { pregQuote } = require('@joplin/lib/string-utils');
@@ -62,7 +62,7 @@ async function createPostFile(post, filePath) {
 		const imagePath = `${tempDir}/${imageFilename}`;
 		const response = await shim.fetchBlob(imageUrl, { path: imagePath, maxRetry: 1 });
 
-		const mimeType = netUtils.mimeTypeFromHeaders(response.headers);
+		const mimeType = mimeTypeFromHeaders(response.headers);
 		let ext = 'jpg';
 		if (mimeType) {
 			const newExt = mimeUtils.toFileExtension(mimeType);