diff --git a/pass/Controllers/GitRepositoryAuthenticationSettingTableViewController.swift b/pass/Controllers/GitRepositoryAuthenticationSettingTableViewController.swift
index 809559b..b2a9578 100644
--- a/pass/Controllers/GitRepositoryAuthenticationSettingTableViewController.swift
+++ b/pass/Controllers/GitRepositoryAuthenticationSettingTableViewController.swift
@@ -18,7 +18,7 @@ class GitRepositoryAuthenticationSettingTableViewController: UITableViewControll
     override func viewDidLoad() {
         super.viewDidLoad()
         navigationItem.title = "Auth Method"
-        switch selectedMethod! {
+        switch selectedMethod ?? "" {
         case "Password":
             passwordCell.accessoryType = UITableViewCellAccessoryType.checkmark
         case "SSH Key":
diff --git a/pass/Controllers/PGPKeySettingTableViewController.swift b/pass/Controllers/PGPKeySettingTableViewController.swift
index 149c5c5..f2663cb 100644
--- a/pass/Controllers/PGPKeySettingTableViewController.swift
+++ b/pass/Controllers/PGPKeySettingTableViewController.swift
@@ -24,6 +24,12 @@ class PGPKeySettingTableViewController: UITableViewController {
     
     override func shouldPerformSegue(withIdentifier identifier: String, sender: Any?) -> Bool {
         if identifier == "savePGPKeySegue" {
+            guard pgpPublicKeyURLTextField.text != nil else {
+                return false
+            }
+            guard pgpPrivateKeyURLTextField.text != nil else {
+                return false
+            }
             if URL(string: pgpPublicKeyURLTextField.text!)!.scheme! == "http" &&
                 URL(string: pgpPrivateKeyURLTextField.text!)!.scheme! == "http" {
                 let alertMessage = "HTTP connection is not supported."
diff --git a/pass/Controllers/SettingsTableViewController.swift b/pass/Controllers/SettingsTableViewController.swift
index 9f88df0..2e3d702 100644
--- a/pass/Controllers/SettingsTableViewController.swift
+++ b/pass/Controllers/SettingsTableViewController.swift
@@ -26,7 +26,11 @@ class SettingsTableViewController: UITableViewController {
     @IBAction func save(segue: UIStoryboardSegue) {
         if let controller = segue.source as? PGPKeySettingTableViewController {
 
-            if Defaults[.pgpKeyID] == nil {
+            if Defaults[.pgpKeyID] == nil ||
+                Defaults[.pgpPrivateKeyURL] != URL(string: controller.pgpPrivateKeyURLTextField.text!) ||
+                Defaults[.pgpPublicKeyURL] != URL(string: controller.pgpPublicKeyURLTextField.text!) ||
+                Defaults[.pgpKeyPassphrase] != controller.pgpKeyPassphraseTextField.text!
+                {
                 Defaults[.pgpPrivateKeyURL] = URL(string: controller.pgpPrivateKeyURLTextField.text!)
                 Defaults[.pgpPublicKeyURL] = URL(string: controller.pgpPublicKeyURLTextField.text!)
                 Defaults[.pgpKeyPassphrase] = controller.pgpKeyPassphraseTextField.text!
diff --git a/pass/Models/PasswordStore.swift b/pass/Models/PasswordStore.swift
index c681cbf..2452d17 100644
--- a/pass/Models/PasswordStore.swift
+++ b/pass/Models/PasswordStore.swift
@@ -80,8 +80,13 @@ class PasswordStore {
         try pgpPrivateData.write(to: URL(fileURLWithPath: pgpPrivateKeyLocalPath), options: .atomic)
         
         pgp.importKeys(fromFile: pgpPublicKeyLocalPath, allowDuplicates: false)
+        if pgp.getKeysOf(.public).count == 0 {
+            throw NSError(domain: "me.mssun.pass.error", code: 2, userInfo: [NSLocalizedDescriptionKey: "Cannot import public key."])
+        }
         pgp.importKeys(fromFile: pgpPrivateKeyLocalPath, allowDuplicates: false)
-
+        if pgp.getKeysOf(.secret).count == 0 {
+            throw NSError(domain: "me.mssun.pass.error", code: 2, userInfo: [NSLocalizedDescriptionKey: "Cannot import seceret key."])
+        }
         let key = pgp.getKeysOf(.public)[0]
         Defaults[.pgpKeyID] = key.keyID!.shortKeyString
         if let gpgUser = key.users[0] as? PGPUser {