diff --git a/app/src/main/java/com/idormy/sms/forwarder/fragment/senders/EmailFragment.kt b/app/src/main/java/com/idormy/sms/forwarder/fragment/senders/EmailFragment.kt
index ca566723..6e05563a 100644
--- a/app/src/main/java/com/idormy/sms/forwarder/fragment/senders/EmailFragment.kt
+++ b/app/src/main/java/com/idormy/sms/forwarder/fragment/senders/EmailFragment.kt
@@ -24,6 +24,7 @@ import com.idormy.sms.forwarder.database.viewmodel.SenderViewModel
 import com.idormy.sms.forwarder.databinding.FragmentSendersEmailBinding
 import com.idormy.sms.forwarder.entity.MsgInfo
 import com.idormy.sms.forwarder.entity.setting.EmailSetting
+import com.idormy.sms.forwarder.utils.Base64
 import com.idormy.sms.forwarder.utils.CommonUtils
 import com.idormy.sms.forwarder.utils.EVENT_TOAST_ERROR
 import com.idormy.sms.forwarder.utils.KEY_SENDER_CLONE
@@ -51,6 +52,7 @@ import io.reactivex.disposables.Disposable
 import io.reactivex.schedulers.Schedulers
 import org.pgpainless.PGPainless
 import org.pgpainless.key.info.KeyRingInfo
+import java.io.ByteArrayInputStream
 import java.io.File
 import java.io.FileInputStream
 import java.security.KeyStore
@@ -377,8 +379,14 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
                         cert.first.isNotEmpty() && cert.second.isNotEmpty() -> {
                             try {
                                 // 判断是否有效的PKCS12私钥证书
+                                val fileInputStream = if (cert.first.startsWith("/")) {
+                                    FileInputStream(cert.first)
+                                } else {
+                                    val decodedBytes = Base64.decode(cert.first)
+                                    ByteArrayInputStream(decodedBytes)
+                                }
                                 val keyStore = KeyStore.getInstance("PKCS12")
-                                keyStore.load(FileInputStream(cert.first), cert.second.toCharArray())
+                                keyStore.load(fileInputStream, cert.second.toCharArray())
                                 val alias = keyStore.aliases().nextElement()
                                 val recipientPublicKey = keyStore.getCertificate(alias) as X509Certificate
                                 Log.d(TAG, "PKCS12 Certificate: $recipientPublicKey")
@@ -391,8 +399,13 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
                         cert.first.isNotEmpty() && cert.second.isEmpty() -> {
                             try {
                                 // 判断是否有效的X.509公钥证书
+                                val fileInputStream = if (cert.first.startsWith("/")) {
+                                    FileInputStream(cert.first)
+                                } else {
+                                    val decodedBytes = Base64.decode(cert.first)
+                                    ByteArrayInputStream(decodedBytes)
+                                }
                                 val certFactory = CertificateFactory.getInstance("X.509")
-                                val fileInputStream = FileInputStream(cert.first)
                                 val recipientPublicKey = certFactory.generateCertificate(fileInputStream) as X509Certificate
                                 Log.d(TAG, "X.509 Certificate: $recipientPublicKey")
                             } catch (e: Exception) {
@@ -408,7 +421,12 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
                         cert.first.isNotEmpty() && cert.second.isNotEmpty() -> {
                             try {
                                 //从私钥证书文件提取公钥
-                                val recipientPrivateKeyStream = FileInputStream(cert.first)
+                                val recipientPrivateKeyStream = if (cert.first.startsWith("/")) {
+                                    FileInputStream(cert.first)
+                                } else {
+                                    val decodedBytes = Base64.decode(cert.first)
+                                    ByteArrayInputStream(decodedBytes)
+                                }
                                 val recipientPGPSecretKeyRing = PGPainless.readKeyRing().secretKeyRing(recipientPrivateKeyStream)
                                 val recipientPGPPublicKeyRing = PGPainless.extractCertificate(recipientPGPSecretKeyRing!!)
                                 val keyInfo = KeyRingInfo(recipientPGPPublicKeyRing)
@@ -422,7 +440,12 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
                         cert.first.isNotEmpty() && cert.second.isEmpty() -> {
                             try {
                                 //从证书文件提取公钥
-                                val recipientPublicKeyStream = FileInputStream(cert.first)
+                                val recipientPublicKeyStream = if (cert.first.startsWith("/")) {
+                                    FileInputStream(cert.first)
+                                } else {
+                                    val decodedBytes = Base64.decode(cert.first)
+                                    ByteArrayInputStream(decodedBytes)
+                                }
                                 val recipientPGPPublicKeyRing = PGPainless.readKeyRing().publicKeyRing(recipientPublicKeyStream)
                                 val keyInfo = KeyRingInfo(recipientPGPPublicKeyRing!!)
                                 Log.d(TAG, "recipientPGPPublicKeyRing: $keyInfo")
@@ -448,7 +471,12 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
         val keystore = binding!!.etSenderKeystore.text.toString().trim()
         val password = binding!!.etSenderPassword.text.toString().trim()
         if (keystore.isNotEmpty()) {
-            val senderPrivateKeyStream = FileInputStream(keystore)
+            val senderPrivateKeyStream = if (keystore.startsWith("/")) {
+                FileInputStream(keystore)
+            } else {
+                val decodedBytes = Base64.decode(keystore)
+                ByteArrayInputStream(decodedBytes)
+            }
             if (senderPrivateKeyStream.available() <= 0) {
                 throw Exception(getString(R.string.invalid_sender_keystore))
             }
@@ -567,12 +595,12 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
                         return
                     }
                     MaterialDialog.Builder(requireContext())
-                        .title(getString(R.string.keystore_path))
+                        .title(getString(R.string.keystore_base64))
                         .content(String.format(getString(R.string.root_directory), downloadPath))
                         .items(fileList)
                         .itemsCallbackSingleChoice(0) { _: MaterialDialog?, _: View?, _: Int, text: CharSequence ->
                             val webPath = "$downloadPath/$text"
-                            etKeyStore.setText(webPath)
+                            etKeyStore.setText(convertCertToBase64String(webPath))
                             true // allow selection
                         }
                         .positiveText(R.string.select)
@@ -614,6 +642,12 @@ class EmailFragment : BaseFragment<FragmentSendersEmailBinding?>(), View.OnClick
         return supportedExtensions.any { it.equals(file.extension, ignoreCase = true) }
     }
 
+    private fun convertCertToBase64String(pfxFilePath: String): String {
+        val pfxInputStream = FileInputStream(pfxFilePath)
+        val pfxBytes = pfxInputStream.readBytes()
+        return Base64.encode(pfxBytes)
+    }
+
     override fun onDestroyView() {
         if (mCountDownHelper != null) mCountDownHelper!!.recycle()
         super.onDestroyView()
diff --git a/app/src/main/java/com/idormy/sms/forwarder/utils/sender/EmailUtils.kt b/app/src/main/java/com/idormy/sms/forwarder/utils/sender/EmailUtils.kt
index 5eb9b3b6..67275562 100644
--- a/app/src/main/java/com/idormy/sms/forwarder/utils/sender/EmailUtils.kt
+++ b/app/src/main/java/com/idormy/sms/forwarder/utils/sender/EmailUtils.kt
@@ -4,6 +4,7 @@ import com.idormy.sms.forwarder.R
 import com.idormy.sms.forwarder.database.entity.Rule
 import com.idormy.sms.forwarder.entity.MsgInfo
 import com.idormy.sms.forwarder.entity.setting.EmailSetting
+import com.idormy.sms.forwarder.utils.Base64
 import com.idormy.sms.forwarder.utils.Log
 import com.idormy.sms.forwarder.utils.SendUtils
 import com.idormy.sms.forwarder.utils.SettingUtils
@@ -16,6 +17,7 @@ import org.bouncycastle.openpgp.PGPPublicKeyRing
 import org.bouncycastle.openpgp.PGPSecretKeyRing
 import org.pgpainless.PGPainless
 import org.pgpainless.key.info.KeyRingInfo
+import java.io.ByteArrayInputStream
 import java.io.FileInputStream
 import java.security.KeyStore
 import java.security.PrivateKey
@@ -166,8 +168,13 @@ class EmailUtils {
                         var senderPGPSecretKeyPassword = ""
 
                         if (!setting.keystore.isNullOrEmpty() && !setting.password.isNullOrEmpty()) {
-                            val keystoreStream = FileInputStream(setting.keystore)
                             try {
+                                val keystoreStream = if (setting.keystore!!.startsWith("/")) {
+                                    FileInputStream(setting.keystore)
+                                } else {
+                                    val decodedBytes = Base64.decode(setting.keystore!!)
+                                    ByteArrayInputStream(decodedBytes)
+                                }
                                 when (setting.encryptionProtocol) {
                                     "S/MIME" -> {
                                         val keystorePassword = setting.password.toString()
@@ -206,15 +213,21 @@ class EmailUtils {
                         //逐一发送加密邮件
                         val recipientsWithoutCert = mutableListOf<String>()
                         setting.recipients.forEach { (email, cert) ->
-                            val keystorePath = cert.first
+                            val keystoreBase64 = cert.first
                             val keystorePassword = cert.second
                             var recipientX509Cert: X509Certificate? = null
                             var recipientPGPPublicKeyRing: PGPPublicKeyRing? = null
                             try {
                                 when {
                                     //从私钥证书文件提取公钥
-                                    keystorePath.isNotEmpty() && keystorePassword.isNotEmpty() -> {
-                                        val keystoreStream = FileInputStream(keystorePath)
+                                    keystoreBase64.isNotEmpty() && keystorePassword.isNotEmpty() -> {
+                                        val keystoreStream = if (keystoreBase64.startsWith("/")) {
+                                            FileInputStream(keystoreBase64)
+                                        } else {
+                                            val decodedBytes = Base64.decode(keystoreBase64)
+                                            ByteArrayInputStream(decodedBytes)
+                                        }
+
                                         when (setting.encryptionProtocol) {
                                             "S/MIME" -> {
                                                 val keyStore = KeyStore.getInstance("PKCS12")
@@ -235,12 +248,18 @@ class EmailUtils {
                                     }
 
                                     //从证书文件提取公钥
-                                    keystorePath.isNotEmpty() && keystorePassword.isEmpty() -> {
-                                        val keystoreStream = FileInputStream(keystorePath)
+                                    keystoreBase64.isNotEmpty() && keystorePassword.isEmpty() -> {
+                                        val keystoreStream = if (keystoreBase64.startsWith("/")) {
+                                            FileInputStream(keystoreBase64)
+                                        } else {
+                                            val decodedBytes = Base64.decode(keystoreBase64)
+                                            ByteArrayInputStream(decodedBytes)
+                                        }
+
                                         when (setting.encryptionProtocol) {
                                             "S/MIME" -> {
                                                 val certFactory = CertificateFactory.getInstance("X.509")
-                                                recipientX509Cert = certFactory.generateCertificate(FileInputStream(keystorePath)) as X509Certificate
+                                                recipientX509Cert = certFactory.generateCertificate(FileInputStream(keystoreBase64)) as X509Certificate
                                             }
 
                                             "OpenPGP" -> {
diff --git a/app/src/main/res/layout/fragment_senders_email.xml b/app/src/main/res/layout/fragment_senders_email.xml
index bbe0f5e0..9baefbd0 100644
--- a/app/src/main/res/layout/fragment_senders_email.xml
+++ b/app/src/main/res/layout/fragment_senders_email.xml
@@ -368,7 +368,7 @@
                     <TextView
                         android:layout_width="wrap_content"
                         android:layout_height="wrap_content"
-                        android:text="@string/keystore_path"
+                        android:text="@string/keystore_base64"
                         android:textSize="@dimen/text_size_small"
                         android:textStyle="bold" />
 
@@ -378,10 +378,13 @@
                         android:layout_height="wrap_content"
                         android:layout_marginStart="5dp"
                         android:layout_weight="1"
-                        android:hint="@string/keystore_path_tips"
+                        android:hint="@string/keystore_base64_tips"
                         android:importantForAutofill="no"
-                        android:singleLine="true"
-                        android:textSize="@dimen/text_size_small"
+                        android:inputType="textMultiLine"
+                        android:maxLines="5"
+                        android:minLines="2"
+                        android:scrollbars="vertical"
+                        android:textSize="@dimen/text_size_mini"
                         app:met_clearButton="true" />
 
                     <com.xuexiang.xui.widget.button.shadowbutton.RippleShadowShadowButton
diff --git a/app/src/main/res/layout/item_add_recipient.xml b/app/src/main/res/layout/item_add_recipient.xml
index 7e1414c8..3cbce8a5 100644
--- a/app/src/main/res/layout/item_add_recipient.xml
+++ b/app/src/main/res/layout/item_add_recipient.xml
@@ -63,7 +63,7 @@
             <TextView
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:text="@string/keystore_path"
+                android:text="@string/keystore_base64"
                 android:textSize="@dimen/text_size_small"
                 android:textStyle="bold" />
 
@@ -73,10 +73,13 @@
                 android:layout_height="wrap_content"
                 android:layout_marginStart="5dp"
                 android:layout_weight="1"
-                android:hint="@string/keystore_path_tips"
+                android:hint="@string/keystore_base64_tips"
                 android:importantForAutofill="no"
-                android:singleLine="true"
-                android:textSize="@dimen/text_size_small"
+                android:inputType="textMultiLine"
+                android:maxLines="5"
+                android:minLines="2"
+                android:scrollbars="vertical"
+                android:textSize="@dimen/text_size_mini"
                 app:met_clearButton="true" />
 
             <com.xuexiang.xui.widget.button.shadowbutton.RippleShadowShadowButton
diff --git a/app/src/main/res/values-en/strings.xml b/app/src/main/res/values-en/strings.xml
index dd9145dc..9beab631 100644
--- a/app/src/main/res/values-en/strings.xml
+++ b/app/src/main/res/values-en/strings.xml
@@ -235,8 +235,8 @@
     <string name="sender_openpgp_keystore">Sender OpenPGP Cert. (Opt.)</string>
     <string name="invalid_sender_keystore">Invalid Sender Signing Private Key</string>
     <string name="recipient_email">Recipient</string>
-    <string name="keystore_path">Cert. Path</string>
-    <string name="keystore_path_tips">Opt., Copy keystore to the Download dir</string>
+    <string name="keystore_base64">Specified Cert.</string>
+    <string name="keystore_base64_tips">Opt., Copy keystore to the Download dir</string>
     <string name="keystore_password">Cert. Pwd.</string>
     <string name="keystore_password_tips">Import password for `Private key`</string>
     <string name="email_title">Email Title</string>
diff --git a/app/src/main/res/values-zh-rCN/strings.xml b/app/src/main/res/values-zh-rCN/strings.xml
index 87766514..bdeae4d4 100644
--- a/app/src/main/res/values-zh-rCN/strings.xml
+++ b/app/src/main/res/values-zh-rCN/strings.xml
@@ -236,8 +236,8 @@
     <string name="sender_openpgp_keystore">发件人OpenPGP签名私钥（可选）</string>
     <string name="invalid_sender_keystore">发件人签名私钥无效</string>
     <string name="recipient_email">收件人邮箱</string>
-    <string name="keystore_path">证书路径</string>
-    <string name="keystore_path_tips">可选，下载证书文件到 Download 目录</string>
+    <string name="keystore_base64">指定证书</string>
+    <string name="keystore_base64_tips">可选，下载证书文件到 Download 目录</string>
     <string name="keystore_password">证书密码</string>
     <string name="keystore_password_tips">`私钥证书`对应的导入密钥</string>
     <string name="email_title">邮件主题</string>
diff --git a/app/src/main/res/values-zh-rTW/strings.xml b/app/src/main/res/values-zh-rTW/strings.xml
index 32d2749c..b419035f 100644
--- a/app/src/main/res/values-zh-rTW/strings.xml
+++ b/app/src/main/res/values-zh-rTW/strings.xml
@@ -236,8 +236,8 @@
     <string name="sender_openpgp_keystore">發件人OpenPGP簽名私鑰（可選）</string>
     <string name="invalid_sender_keystore">發件人簽名私鑰無效</string>
     <string name="recipient_email">收件人郵箱</string>
-    <string name="keystore_path">證書路徑</string>
-    <string name="keystore_path_tips">可選，下載證書文件到 Download 目錄</string>
+    <string name="keystore_base64">指定證書</string>
+    <string name="keystore_base64_tips">可選，下載證書文件到 Download 目錄</string>
     <string name="keystore_password">證書密碼</string>
     <string name="keystore_password_tips">「私鑰證書」相對應的導入密碼</string>
     <string name="email_title">郵件主題</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index ef601db0..c9e6d42b 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -262,8 +262,8 @@
     <string name="sender_openpgp_keystore">发件人OpenPGP签名私钥（可选）</string>
     <string name="invalid_sender_keystore">发件人签名私钥无效</string>
     <string name="recipient_email">收件人邮箱</string>
-    <string name="keystore_path">证书路径</string>
-    <string name="keystore_path_tips">可选，下载证书文件到 Download 目录</string>
+    <string name="keystore_base64">指定证书</string>
+    <string name="keystore_base64_tips">可选，下载证书文件到 Download 目录</string>
     <string name="keystore_password">证书密码</string>
     <string name="keystore_password_tips">`私钥证书`对应的导入密钥</string>
     <string name="email_title">邮件主题</string>