diff --git a/app/src/main/java/io/nekohasekai/sagernet/ui/MainActivity.kt b/app/src/main/java/io/nekohasekai/sagernet/ui/MainActivity.kt
index 55b2acab..387c8c80 100644
--- a/app/src/main/java/io/nekohasekai/sagernet/ui/MainActivity.kt
+++ b/app/src/main/java/io/nekohasekai/sagernet/ui/MainActivity.kt
@@ -36,9 +36,7 @@ import io.nekohasekai.sagernet.group.GroupInterfaceAdapter
 import io.nekohasekai.sagernet.group.GroupUpdater
 import io.nekohasekai.sagernet.ktx.*
 import io.nekohasekai.sagernet.widget.ListHolderListener
-import libcore.Libcore
 import moe.matsuri.nb4a.utils.Util
-import java.text.SimpleDateFormat
 import java.util.*
 
 class MainActivity : ThemedActivity(),
@@ -465,42 +463,4 @@ class MainActivity : ThemedActivity(),
         return fragment != null && fragment.onKeyDown(keyCode, event)
     }
 
-    @SuppressLint("SimpleDateFormat")
-    override fun onResume() {
-        super.onResume()
-
-        val sdf = SimpleDateFormat("yyyy-MM-dd")
-        val now = System.currentTimeMillis()
-        val expire = Libcore.getExpireTime() * 1000
-        val dateExpire = Date(expire)
-        val build = Libcore.getBuildTime() * 1000
-        val dateBuild = Date(build)
-
-        var text: String? = null
-        if (now > expire) {
-            text = getString(
-                R.string.please_update_force, sdf.format(dateBuild), sdf.format(dateExpire)
-            )
-        } else if (now > (expire - 2592000000)) {
-            // 30 days remind :D
-            text = getString(
-                R.string.please_update, sdf.format(dateBuild), sdf.format(dateExpire)
-            )
-        }
-
-
-        if (text != null) {
-            MaterialAlertDialogBuilder(this@MainActivity).setTitle(R.string.insecure)
-                .setMessage(text)
-                .setPositiveButton(R.string.action_download) { _, _ ->
-                    launchCustomTab(
-                        "https://github.com/MatsuriDayo/NekoBoxForAndroid/releases"
-                    )
-                }
-                .setNegativeButton(android.R.string.cancel, null)
-                .setCancelable(false)
-                .show()
-        }
-    }
-
 }
diff --git a/libcore/box.go b/libcore/box.go
index f373af11..b250ae0c 100644
--- a/libcore/box.go
+++ b/libcore/box.go
@@ -118,10 +118,6 @@ func NewSingBoxInstance(config string) (b *BoxInstance, err error) {
 func (b *BoxInstance) Start() (err error) {
 	defer device.DeferPanicToError("box.Start", func(err_ error) { err = err_ })
 
-	if outdated != "" {
-		return errors.New(outdated)
-	}
-
 	if b.state == 0 {
 		b.state = 1
 		return b.Box.Start()
diff --git a/libcore/date.go b/libcore/date.go
deleted file mode 100644
index 5bab1a65..00000000
--- a/libcore/date.go
+++ /dev/null
@@ -1,20 +0,0 @@
-package libcore
-
-import (
-	"strconv"
-	"time"
-)
-
-var outdated string
-
-func GetBuildTime() int64 {
-	buildDate := 20231005
-	buildTime, _ := time.Parse("20060102", strconv.Itoa(buildDate))
-	return buildTime.Unix()
-}
-
-func GetExpireTime() int64 {
-	buildTime := time.Unix(GetBuildTime(), 0)
-	expireTime := buildTime.AddDate(0, 6, 0) // current force update: 6 months
-	return expireTime.Unix()
-}
diff --git a/libcore/nb4a.go b/libcore/nb4a.go
index d22fbe24..97ae290d 100644
--- a/libcore/nb4a.go
+++ b/libcore/nb4a.go
@@ -6,7 +6,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
-	"time"
 	_ "unsafe"
 
 	"log"
@@ -72,10 +71,6 @@ func InitCore(process, cachePath, internalAssets, externalAssets string,
 		externalAssetsPath = externalAssets
 		internalAssetsPath = internalAssets
 
-		if time.Now().Unix() >= GetExpireTime() {
-			outdated = "Your version is too old! Please update!! 版本太旧，请升级！"
-		}
-
 		// certs
 		pem, err := os.ReadFile(externalAssetsPath + "ca.pem")
 		if err == nil {