diff --git a/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAccountPane.java b/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAccountPane.java
index c4aeb0b3a..6277b9129 100644
--- a/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAccountPane.java
+++ b/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAccountPane.java
@@ -31,6 +31,7 @@ import javafx.scene.layout.BorderPane;
 import javafx.scene.layout.HBox;
 import javafx.scene.layout.StackPane;
 import org.jackhuang.hmcl.auth.*;
+import org.jackhuang.hmcl.auth.authlibinjector.AuthlibInjectorDownloadException;
 import org.jackhuang.hmcl.auth.authlibinjector.AuthlibInjectorServer;
 import org.jackhuang.hmcl.auth.yggdrasil.GameProfile;
 import org.jackhuang.hmcl.auth.yggdrasil.RemoteAuthenticationException;
@@ -278,6 +279,8 @@ public class AddAccountPane extends StackPane {
                     return i18n("account.failed.invalid_password");
             }
             return exception.getMessage();
+        } else if (exception instanceof AuthlibInjectorDownloadException) {
+            return i18n("account.failed.injector_download_failure");
         } else {
             return exception.getClass().getName() + ": " + exception.getLocalizedMessage();
         }
diff --git a/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAuthlibInjectorServerPane.java b/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAuthlibInjectorServerPane.java
index 7ad0ce437..2235e94c0 100644
--- a/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAuthlibInjectorServerPane.java
+++ b/HMCL/src/main/java/org/jackhuang/hmcl/ui/account/AddAuthlibInjectorServerPane.java
@@ -21,7 +21,6 @@ import com.jfoenix.controls.JFXButton;
 import com.jfoenix.controls.JFXDialogLayout;
 import com.jfoenix.controls.JFXTextField;
 
-import javafx.beans.binding.Bindings;
 import javafx.fxml.FXML;
 import javafx.scene.control.Label;
 import javafx.scene.layout.StackPane;
@@ -39,7 +38,6 @@ import java.io.IOException;
 
 import static org.jackhuang.hmcl.setting.ConfigHolder.config;
 import static org.jackhuang.hmcl.ui.FXUtils.loadFXML;
-import static org.jackhuang.hmcl.util.Lang.thread;
 import static org.jackhuang.hmcl.util.i18n.I18n.i18n;
 
 public class AddAuthlibInjectorServerPane extends StackPane implements DialogAware {
@@ -70,24 +68,13 @@ public class AddAuthlibInjectorServerPane extends StackPane implements DialogAwa
         transitionHandler = new TransitionHandler(addServerContainer);
         transitionHandler.setContent(addServerPane, ContainerAnimations.NONE.getAnimationProducer());
 
-        btnAddNext.disableProperty().bind(
-                Bindings.createBooleanBinding(txtServerUrl::validate, txtServerUrl.textProperty()).not());
+        btnAddNext.disableProperty().bind(txtServerUrl.textProperty().isEmpty());
         nextPane.hideSpinner();
-
-        txtServerUrl.setText("https://");
     }
 
     @Override
     public void onDialogShown() {
         txtServerUrl.requestFocus();
-        txtServerUrl.selectEnd();
-    }
-
-    private String fixInputUrl(String url) {
-        if (!url.endsWith("/")) {
-            url += "/";
-        }
-        return url;
     }
 
     private String resolveFetchExceptionMessage(Throwable exception) {
@@ -110,13 +97,13 @@ public class AddAuthlibInjectorServerPane extends StackPane implements DialogAwa
 
         lblCreationWarning.setText("");
 
-        String url = fixInputUrl(txtServerUrl.getText());
+        String url = txtServerUrl.getText();
 
         nextPane.showSpinner();
         addServerPane.setDisable(true);
 
         Task.of(() -> {
-            serverBeingAdded = AuthlibInjectorServer.fetchServerInfo(url);
+            serverBeingAdded = AuthlibInjectorServer.locateServer(url);
         }).finalized(Schedulers.javafx(), (variables, isDependentsSucceeded) -> {
             addServerPane.setDisable(false);
             nextPane.hideSpinner();
diff --git a/HMCL/src/main/java/org/jackhuang/hmcl/ui/construct/URLValidator.java b/HMCL/src/main/java/org/jackhuang/hmcl/ui/construct/URLValidator.java
deleted file mode 100644
index 87a5f38fa..000000000
--- a/HMCL/src/main/java/org/jackhuang/hmcl/ui/construct/URLValidator.java
+++ /dev/null
@@ -1,37 +0,0 @@
-package org.jackhuang.hmcl.ui.construct;
-
-import com.jfoenix.validation.base.ValidatorBase;
-import javafx.collections.FXCollections;
-import javafx.collections.ObservableList;
-import javafx.scene.control.TextInputControl;
-
-import java.net.MalformedURLException;
-import java.net.URL;
-
-public class URLValidator extends ValidatorBase {
-
-    private final ObservableList<String> protocols = FXCollections.observableArrayList();
-
-    public URLValidator() {
-        super();
-    }
-
-    public ObservableList<String> getProtocols() {
-        return protocols;
-    }
-
-    @Override
-    protected void eval() {
-        if (srcControl.get() instanceof TextInputControl) {
-            try {
-                URL url = new URL(((TextInputControl) srcControl.get()).getText());
-                if (protocols.isEmpty())
-                    hasErrors.set(false);
-                else
-                    hasErrors.set(!protocols.contains(url.getProtocol()));
-            } catch (MalformedURLException e) {
-                hasErrors.set(true);
-            }
-        }
-    }
-}
diff --git a/HMCL/src/main/resources/assets/fxml/authlib-injector-server-add.fxml b/HMCL/src/main/resources/assets/fxml/authlib-injector-server-add.fxml
index e060d182e..6065f6fe1 100644
--- a/HMCL/src/main/resources/assets/fxml/authlib-injector-server-add.fxml
+++ b/HMCL/src/main/resources/assets/fxml/authlib-injector-server-add.fxml
@@ -4,7 +4,6 @@
 <?import javafx.scene.control.*?>
 <?import javafx.scene.layout.*?>
 <?import com.jfoenix.controls.*?>
-<?import org.jackhuang.hmcl.ui.construct.URLValidator?>
 <?import org.jackhuang.hmcl.ui.construct.SpinnerPane?>
 
 <fx:root xmlns="http://javafx.com/javafx"
@@ -16,16 +15,7 @@
                 <Label text="%account.injector.add" />
             </heading>
             <body>
-                <JFXTextField fx:id="txtServerUrl" promptText="%account.injector.server_url" onAction="#onAddNext">
-                    <validators>
-                        <URLValidator message="%input.url">
-                            <protocols>
-                                <String fx:value="http" />
-                                <String fx:value="https" />
-                            </protocols>
-                        </URLValidator>
-                    </validators>
-                </JFXTextField>
+                <JFXTextField fx:id="txtServerUrl" promptText="%account.injector.server_url" onAction="#onAddNext" />
             </body>
             <actions>
                 <Label fx:id="lblCreationWarning" />
diff --git a/HMCL/src/main/resources/assets/lang/I18N.properties b/HMCL/src/main/resources/assets/lang/I18N.properties
index cabeb15d9..3a6c46f07 100644
--- a/HMCL/src/main/resources/assets/lang/I18N.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N.properties
@@ -36,6 +36,7 @@ account.create=Create a new account
 account.email=Email
 account.failed.connect_authentication_server=Cannot connect to the authentication server. Check your network.
 account.failed.connect_injector_server=Cannot connect to the authentication server. Check your network and ensure the URL is correct.
+account.failed.injector_download_failure=Failed to download authlib-injector. Check your network and try switching to another download source.
 account.failed.invalid_credentials=Incorrect password, or you are forbidden to login temporarily.
 account.failed.invalid_password=Invalid password
 account.failed.invalid_token=Please log out and re-input your password to login.
diff --git a/HMCL/src/main/resources/assets/lang/I18N_zh.properties b/HMCL/src/main/resources/assets/lang/I18N_zh.properties
index 276da5f6a..990c372c9 100644
--- a/HMCL/src/main/resources/assets/lang/I18N_zh.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N_zh.properties
@@ -36,6 +36,7 @@ account.create=建立帳戶
 account.email=電子信箱
 account.failed.connect_authentication_server=無法連接認證伺服器，可能是網路問題
 account.failed.connect_injector_server=無法連接認證伺服器，可能是網路故障或 URL 輸入錯誤
+account.failed.injector_download_failure=無法下載 authlib-injector，請檢查網路或嘗試切換下載源
 account.failed.invalid_credentials=您的使用者名稱或密碼錯誤，或者登入次數過多被暫時禁止登入，請稍後再試
 account.failed.invalid_password=無效的密碼
 account.failed.invalid_token=請嘗試登出並重新輸入密碼登入
diff --git a/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties b/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties
index 81ad563ac..fc92eb93f 100644
--- a/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties
@@ -36,6 +36,7 @@ account.create=新建账户
 account.email=邮箱
 account.failed.connect_authentication_server=无法连接认证服务器，可能是网络问题
 account.failed.connect_injector_server=无法连接认证服务器，可能是网络故障或 URL 输入错误
+account.failed.injector_download_failure=无法下载 authlib-injector，请检查网络或尝试切换下载源
 account.failed.invalid_credentials=您的用户名或密码错误，或者登录次数过多被暂时禁止登录，请稍后再试
 account.failed.invalid_password=无效的密码
 account.failed.invalid_token=请尝试登出并重新输入密码登录
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorAccount.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorAccount.java
index 39ba2f071..4d95fb41d 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorAccount.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorAccount.java
@@ -20,21 +20,20 @@ package org.jackhuang.hmcl.auth.authlibinjector;
 import org.jackhuang.hmcl.auth.AuthInfo;
 import org.jackhuang.hmcl.auth.AuthenticationException;
 import org.jackhuang.hmcl.auth.CharacterSelector;
+import org.jackhuang.hmcl.auth.ServerDisconnectException;
 import org.jackhuang.hmcl.auth.yggdrasil.YggdrasilAccount;
 import org.jackhuang.hmcl.auth.yggdrasil.YggdrasilService;
 import org.jackhuang.hmcl.auth.yggdrasil.YggdrasilSession;
 import org.jackhuang.hmcl.game.Arguments;
-import org.jackhuang.hmcl.task.GetTask;
-import org.jackhuang.hmcl.util.Lang;
 import org.jackhuang.hmcl.util.function.ExceptionalSupplier;
-import org.jackhuang.hmcl.util.io.NetworkUtils;
-
 import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
 import java.util.*;
-import java.util.logging.Level;
-
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.jackhuang.hmcl.util.Logging.LOG;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.ExecutionException;
+import static org.jackhuang.hmcl.util.io.IOUtils.readFullyWithoutClosing;
 
 public class AuthlibInjectorAccount extends YggdrasilAccount {
     private AuthlibInjectorServer server;
@@ -58,41 +57,44 @@ public class AuthlibInjectorAccount extends YggdrasilAccount {
     }
 
     private AuthInfo inject(ExceptionalSupplier<AuthInfo, AuthenticationException> loginAction) throws AuthenticationException {
-        // Pre-fetch metadata
-        GetTask metadataFetchTask = new GetTask(NetworkUtils.toURL(server.getUrl()));
-        Thread metadataFetchThread = Lang.thread(() -> {
-            try {
-                metadataFetchTask.run();
-            } catch (Exception e) {
-                LOG.log(Level.WARNING, "Failed to pre-fetch Yggdrasil metadata", e);
+        CompletableFuture<byte[]> prefetchedMetaTask = CompletableFuture.supplyAsync(() -> {
+            try (InputStream in = new URL(server.getUrl()).openStream()) {
+                return readFullyWithoutClosing(in);
+            } catch (IOException e) {
+                throw new CompletionException(new ServerDisconnectException(e));
             }
-        }, "Yggdrasil metadata fetch thread");
+        });
 
-        // Update authlib-injector
+        CompletableFuture<AuthlibInjectorArtifactInfo> artifactTask = CompletableFuture.supplyAsync(() -> {
+            try {
+                return authlibInjectorDownloader.get();
+            } catch (IOException e) {
+                throw new CompletionException(new AuthlibInjectorDownloadException(e));
+            }
+        });
+
+        AuthInfo auth = loginAction.get();
+        byte[] prefetchedMeta;
         AuthlibInjectorArtifactInfo artifact;
-        try {
-            artifact = authlibInjectorDownloader.get();
-        } catch (IOException e) {
-            throw new AuthenticationException("Failed to download authlib-injector", e);
-        }
 
-        // Perform authentication
-        AuthInfo info = loginAction.get();
-        Arguments arguments = new Arguments().addJVMArguments("-javaagent:" + artifact.getLocation().toString() + "=" + server.getUrl());
-
-        // Wait for metadata to be fetched
         try {
-            metadataFetchThread.join();
+            prefetchedMeta = prefetchedMetaTask.get();
+            artifact = artifactTask.get();
         } catch (InterruptedException e) {
             Thread.currentThread().interrupt();
-        }
-        Optional<String> metadata = Optional.ofNullable(metadataFetchTask.getResult());
-        if (metadata.isPresent()) {
-            arguments = arguments.addJVMArguments(
-                    "-Dorg.to2mbn.authlibinjector.config.prefetched=" + Base64.getEncoder().encodeToString(metadata.get().getBytes(UTF_8)));
+            throw new AuthenticationException(e);
+        } catch (ExecutionException e) {
+            if (e.getCause() instanceof AuthenticationException) {
+                throw (AuthenticationException) e.getCause();
+            } else {
+                throw new AuthenticationException(e.getCause());
+            }
         }
 
-        return info.withArguments(arguments);
+        return auth.withArguments(new Arguments().addJVMArguments(
+                "-javaagent:" + artifact.getLocation().toString() + "=" + server.getUrl(),
+                "-Dauthlibinjector.side=client",
+                "-Dorg.to2mbn.authlibinjector.config.prefetched=" + Base64.getEncoder().encodeToString(prefetchedMeta)));
     }
 
     @Override
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloadException.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloadException.java
new file mode 100644
index 000000000..3b8dd3683
--- /dev/null
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloadException.java
@@ -0,0 +1,41 @@
+/*
+ * Hello Minecraft! Launcher.
+ * Copyright (C) 2018  huangyuhui <huanghongxun2008@126.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see {http://www.gnu.org/licenses/}.
+ */
+package org.jackhuang.hmcl.auth.authlibinjector;
+
+import org.jackhuang.hmcl.auth.AuthenticationException;
+
+/**
+ * @author yushijinhun
+ */
+public class AuthlibInjectorDownloadException extends AuthenticationException {
+
+    public AuthlibInjectorDownloadException() {
+    }
+
+    public AuthlibInjectorDownloadException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public AuthlibInjectorDownloadException(String message) {
+        super(message);
+    }
+
+    public AuthlibInjectorDownloadException(Throwable cause) {
+        super(cause);
+    }
+}
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloader.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloader.java
index f2f0c539e..fb7201037 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloader.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorDownloader.java
@@ -45,6 +45,11 @@ public class AuthlibInjectorDownloader {
     private Path artifactLocation;
     private Supplier<DownloadProvider> downloadProvider;
 
+    /**
+     * The flag will be reset after application restart.
+     */
+    private boolean updateChecked = false;
+
     /**
      * @param artifactsDirectory where to save authlib-injector artifacts
      */
@@ -57,14 +62,17 @@ public class AuthlibInjectorDownloader {
         synchronized (artifactLocation) {
             Optional<AuthlibInjectorArtifactInfo> local = getLocalArtifact();
 
-            try {
-                update(local);
-            } catch (IOException e) {
-                LOG.log(Level.WARNING, "Failed to download authlib-injector", e);
-                if (!local.isPresent()) {
-                    throw e;
+            if (!local.isPresent() || !updateChecked) {
+                try {
+                    update(local);
+                    updateChecked = true;
+                } catch (IOException e) {
+                    LOG.log(Level.WARNING, "Failed to download authlib-injector", e);
+                    if (!local.isPresent()) {
+                        throw e;
+                    }
+                    LOG.warning("Fallback to use cached artifact: " + local.get());
                 }
-                LOG.warning("Fallback to use cached artifact: " + local.get());
             }
 
             return getLocalArtifact().orElseThrow(() -> new IOException("The updated authlib-inejector cannot be recognized"));
@@ -72,6 +80,7 @@ public class AuthlibInjectorDownloader {
     }
 
     private void update(Optional<AuthlibInjectorArtifactInfo> local) throws IOException {
+        LOG.info("Checking update of authlib-injector");
         AuthlibInjectorVersionInfo latest = getLatestArtifactInfo();
 
         if (local.isPresent() && local.get().getBuildNumber() >= latest.buildNumber) {
diff --git a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorServer.java b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorServer.java
index 015c4b00b..0c4decdcc 100644
--- a/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorServer.java
+++ b/HMCLCore/src/main/java/org/jackhuang/hmcl/auth/authlibinjector/AuthlibInjectorServer.java
@@ -17,23 +17,104 @@
  */
 package org.jackhuang.hmcl.auth.authlibinjector;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.jackhuang.hmcl.util.Lang.tryCast;
+import static org.jackhuang.hmcl.util.Logging.LOG;
+import static org.jackhuang.hmcl.util.io.IOUtils.readFullyWithoutClosing;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.Optional;
+
+import org.jackhuang.hmcl.util.gson.JsonUtils;
+
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParseException;
 import com.google.gson.JsonPrimitive;
 
-import org.jackhuang.hmcl.util.gson.JsonUtils;
-import org.jackhuang.hmcl.util.io.NetworkUtils;
-
-import java.io.IOException;
-import java.util.Optional;
-
-import static org.jackhuang.hmcl.util.Lang.tryCast;
-
 public class AuthlibInjectorServer {
 
-    public static AuthlibInjectorServer fetchServerInfo(String url) throws IOException {
+    private static final int MAX_REDIRECTS = 5;
+
+    public static AuthlibInjectorServer locateServer(String url) throws IOException {
+        url = parseInputUrl(url);
+        HttpURLConnection conn;
+        int redirectCount = 0;
+        for (;;) {
+            conn = (HttpURLConnection) new URL(url).openConnection();
+            Optional<String> ali = getApiLocationIndication(conn);
+            if (ali.isPresent()) {
+                conn.disconnect();
+                url = ali.get();
+                if (redirectCount >= MAX_REDIRECTS) {
+                    throw new IOException("Exceeded maximum number of redirects (" + MAX_REDIRECTS + ")");
+                }
+                redirectCount++;
+                LOG.info("Redirect API root to: " + url);
+            } else {
+                break;
+            }
+        }
+
         try {
-            JsonObject response = JsonUtils.fromNonNullJson(NetworkUtils.doGet(NetworkUtils.toURL(url)), JsonObject.class);
+            return parseResponse(url, readFullyWithoutClosing(conn.getInputStream()));
+        } finally {
+            conn.disconnect();
+        }
+    }
+
+    private static Optional<String> getApiLocationIndication(URLConnection conn) {
+        return Optional.ofNullable(conn.getHeaderFields().get("X-Authlib-Injector-API-Location"))
+                .flatMap(list -> list.isEmpty() ? Optional.empty() : Optional.of(list.get(0)))
+                .flatMap(indication -> {
+                    String currentUrl = appendSuffixSlash(conn.getURL().toString());
+                    String newUrl;
+                    try {
+                        newUrl = appendSuffixSlash(new URL(conn.getURL(), indication).toString());
+                    } catch (MalformedURLException e) {
+                        LOG.warning("Failed to resolve absolute ALI, the header is [" + indication + "]. Ignore it.");
+                        return Optional.empty();
+                    }
+
+                    if (newUrl.equals(currentUrl)) {
+                        return Optional.empty();
+                    } else {
+                        return Optional.of(newUrl);
+                    }
+                });
+    }
+
+    private static String parseInputUrl(String url) {
+        String lowercased = url.toLowerCase();
+        if (!lowercased.startsWith("http://") && !lowercased.startsWith("https://")) {
+            url = "https://" + url;
+        }
+
+        url = appendSuffixSlash(url);
+        return url;
+    }
+
+    private static String appendSuffixSlash(String url) {
+        if (!url.endsWith("/")) {
+            return url + "/";
+        } else {
+            return url;
+        }
+    }
+
+    public static AuthlibInjectorServer fetchServerInfo(String url) throws IOException {
+        try (InputStream in = new URL(url).openStream()) {
+            return parseResponse(url, readFullyWithoutClosing(in));
+        }
+    }
+
+    private static AuthlibInjectorServer parseResponse(String url, byte[] rawResponse) throws IOException {
+        try {
+            JsonObject response = JsonUtils.fromNonNullJson(new String(rawResponse, UTF_8), JsonObject.class);
             String name = extractServerName(response).orElse(url);
             return new AuthlibInjectorServer(url, name);
         } catch (JsonParseException e) {