diff --git a/HMCL/src/main/java/org/jackhuang/hmcl/Launcher.java b/HMCL/src/main/java/org/jackhuang/hmcl/Launcher.java
index cf8c429fa..af1189675 100644
--- a/HMCL/src/main/java/org/jackhuang/hmcl/Launcher.java
+++ b/HMCL/src/main/java/org/jackhuang/hmcl/Launcher.java
@@ -70,6 +70,10 @@ public final class Launcher extends Application {
                 Main.showErrorAndExit(i18n("fatal.config_loading_failure", Paths.get("").toAbsolutePath().normalize()));
             }
 
+            if (Metadata.HMCL_DIRECTORY.toAbsolutePath().toString().indexOf('=') >= 0) {
+                Main.showWarningAndContinue(i18n("fatal.illegal_char"));
+            }
+
             // runLater to ensure ConfigHolder.init() finished initialization
             Platform.runLater(() -> {
                 // When launcher visibility is set to "hide and reopen" without Platform.implicitExit = false,
diff --git a/HMCL/src/main/resources/assets/lang/I18N.properties b/HMCL/src/main/resources/assets/lang/I18N.properties
index 45cd14dc3..bf6f7b1cf 100644
--- a/HMCL/src/main/resources/assets/lang/I18N.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N.properties
@@ -314,6 +314,7 @@ fatal.config_loading_failure=The configuration is not accessible.\nPlease ensure
 fatal.migration_requires_manual_reboot=The update is complete. Please reopen Hello Minecraft! Launcher.
 fatal.apply_update_failure=We're sorry, Hello Minecraft! Launcher couldn't finish the update because something went wrong.\nBut you can still manually finish the update by downloading Hello Minecraft! Launcher from %s.\nPlease consider reporting this issue to us.
 fatal.samba=If you are trying to run HMCL in a shared folder by Samba, HMCL may not working, please try updating your Java or running HMCL in a local folder.
+fatal.illegal_char=Illegal character '=' in your user folder path. HMCL can work, but some features don't work.\nYou will not be able to use the authlib-injector account or changing skin of offline account, and there may be greater security risks in multiplayer games.
 
 feedback=Feedback
 feedback.add=Add Feedback
diff --git a/HMCL/src/main/resources/assets/lang/I18N_zh.properties b/HMCL/src/main/resources/assets/lang/I18N_zh.properties
index 8a1c1ea0b..f74d89f64 100644
--- a/HMCL/src/main/resources/assets/lang/I18N_zh.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N_zh.properties
@@ -314,6 +314,7 @@ fatal.config_loading_failure=Hello Minecraft! Launcher 無法載入設定檔案
 fatal.migration_requires_manual_reboot=Hello Minecraft! Launcher 即將升級完成，請重新開啟 Hello Minecraft! Launcher。
 fatal.apply_update_failure=我們很抱歉 Hello Minecraft! Launcher 無法自動完成升級程式，因為出現了一些問題。\n但你依然可以從 %s 處手動下載 Hello Minecraft! Launcher 來完成升級。\n請考慮向我們回報該問題。
 fatal.samba=如果您正在通過 Samba 共亯的資料夾中運行 HMCL，HMCL 可能無法正常工作，請嘗試更新您的 Java 或在本地資料夾內運行 HMCL。
+fatal.illegal_char=您的用戶資料夾路徑中存在非法字元‘=’。HMCL 能够運行，但一些功能無法正常使用。 \n您將無法使用外置登入帳戶以及離線登入更換皮膚功能，並且在進行多人遊戲時可能存在更大的安全隱患。
 
 feedback=回饋
 feedback.add=新增回饋
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 f08327f14..936997328 100644
--- a/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties
+++ b/HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties
@@ -314,6 +314,7 @@ fatal.config_loading_failure=Hello Minecraft! Launcher 无法加载配置文件
 fatal.migration_requires_manual_reboot=Hello Minecraft! Launcher 即将完成升级，请重新打开 Hello Minecraft! Launcher。
 fatal.apply_update_failure=我们很抱歉 Hello Minecraft! Launcher 无法自动完成升级，因为出现了一些问题。\n但你依然可以从 %s 处手动下载 Hello Minecraft! Launcher 来完成升级。\n请考虑向我们反馈该问题。
 fatal.samba=如果您正在通过 Samba 共享的文件夹中运行 HMCL，HMCL 可能无法正常工作，请尝试更新您的 Java 或在本地文件夹内运行 HMCL。
+fatal.illegal_char=您的用户文件夹路径中存在非法字符‘=’。HMCL 能够运行，但一些功能无法正常使用。\n您将无法使用外置登陆账户以及离线登陆更换皮肤功能，并且在进行多人游戏时可能存在更大的安全隐患。
 
 feedback=反馈
 feedback.add=新增反馈