diff --git a/src/main/scala/gitbucket/core/controller/AccountController.scala b/src/main/scala/gitbucket/core/controller/AccountController.scala
index 0b71485..12ec24e 100644
--- a/src/main/scala/gitbucket/core/controller/AccountController.scala
+++ b/src/main/scala/gitbucket/core/controller/AccountController.scala
@@ -179,8 +179,8 @@
     val userName = params("userName")
 
     getAccountByUserName(userName, true).map { account =>
-      if(isLastAdministrator(userName)){
-        flash += "error" -> "Account can't be removed because this is the last administrator."
+      if(isLastAdministrator(account)){
+        flash += "error" -> "Account can't be removed because this is last one administrator."
         redirect(s"/${userName}/_edit")
       } else {
 //      // Remove repositories
diff --git a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
index ed578d0..ded55b3 100644
--- a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
+++ b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
@@ -179,36 +179,39 @@
 
   get("/admin/users/:userName/_edituser")(adminOnly {
     val userName = params("userName")
-    html.user(getAccountByUserName(userName, true))
+    html.user(getAccountByUserName(userName, true), flash.get("error"))
   })
 
   post("/admin/users/:name/_edituser", editUserForm)(adminOnly { form =>
     val userName = params("userName")
     getAccountByUserName(userName, true).map { account =>
+      if(account.isAdmin && (form.isRemoved || !form.isAdmin) && isLastAdministrator(account)){
+        flash += "error" -> "Account can't be turned off because this is last one administrator."
+        redirect(s"/admin/users/${userName}/_edituser")
+      } else {
+        if(form.isRemoved){
+          // Remove repositories
+          //        getRepositoryNamesOfUser(userName).foreach { repositoryName =>
+          //          deleteRepository(userName, repositoryName)
+          //          FileUtils.deleteDirectory(getRepositoryDir(userName, repositoryName))
+          //          FileUtils.deleteDirectory(getWikiRepositoryDir(userName, repositoryName))
+          //          FileUtils.deleteDirectory(getTemporaryDir(userName, repositoryName))
+          //        }
+          // Remove from GROUP_MEMBER, COLLABORATOR and REPOSITORY
+          removeUserRelatedData(userName)
+        }
 
-      if(form.isRemoved){
-        // Remove repositories
-        //        getRepositoryNamesOfUser(userName).foreach { repositoryName =>
-        //          deleteRepository(userName, repositoryName)
-        //          FileUtils.deleteDirectory(getRepositoryDir(userName, repositoryName))
-        //          FileUtils.deleteDirectory(getWikiRepositoryDir(userName, repositoryName))
-        //          FileUtils.deleteDirectory(getTemporaryDir(userName, repositoryName))
-        //        }
-        // Remove from GROUP_MEMBER, COLLABORATOR and REPOSITORY
-        removeUserRelatedData(userName)
+        updateAccount(account.copy(
+          password     = form.password.map(sha1).getOrElse(account.password),
+          fullName     = form.fullName,
+          mailAddress  = form.mailAddress,
+          isAdmin      = form.isAdmin,
+          url          = form.url,
+          isRemoved    = form.isRemoved))
+
+        updateImage(userName, form.fileId, form.clearImage)
+        redirect("/admin/users")
       }
-
-      updateAccount(account.copy(
-        password     = form.password.map(sha1).getOrElse(account.password),
-        fullName     = form.fullName,
-        mailAddress  = form.mailAddress,
-        isAdmin      = form.isAdmin,
-        url          = form.url,
-        isRemoved    = form.isRemoved))
-
-      updateImage(userName, form.fileId, form.clearImage)
-      redirect("/admin/users")
-
     } getOrElse NotFound
   })
 
diff --git a/src/main/scala/gitbucket/core/service/AccountService.scala b/src/main/scala/gitbucket/core/service/AccountService.scala
index 5325787..04d7a41 100644
--- a/src/main/scala/gitbucket/core/service/AccountService.scala
+++ b/src/main/scala/gitbucket/core/service/AccountService.scala
@@ -97,10 +97,10 @@
       Accounts filter (_.removed === false.bind) sortBy(_.userName) list
     }
 
-  def isLastAdministrator(userName: String)(implicit s: Session): Boolean = {
-    getAccountByUserName(userName).collect { case account if account.isAdmin =>
+  def isLastAdministrator(account: Account)(implicit s: Session): Boolean = {
+    if(account.isAdmin){
       (Accounts filter (_.removed === false.bind) filter (_.isAdmin === true.bind) map (_.userName.length)).first == 1
-    } getOrElse false
+    } else false
   }
 
   def createAccount(userName: String, password: String, fullName: String, mailAddress: String, isAdmin: Boolean, url: Option[String])
diff --git a/src/main/twirl/gitbucket/core/account/register.scala.html b/src/main/twirl/gitbucket/core/account/register.scala.html
index 94f95ab..8dc7c59 100644
--- a/src/main/twirl/gitbucket/core/account/register.scala.html
+++ b/src/main/twirl/gitbucket/core/account/register.scala.html
@@ -2,36 +2,36 @@
 @import context._
 @import gitbucket.core.view.helpers._
 @html.main("Create your account"){
-<div class="container body">
+<div class="container body main-center">
   <h3>Create your account</h3>
   <form action="@path/register" method="POST" validate="true">
     <div class="row">
       <div class="col-md-6">
         <fieldset>
           <label for="userName" class="strong">Username:</label>
-          <input type="text" name="userName" id="userName" value="" autofocus/>
+          <input type="text" name="userName" id="userName" value="" class="form-control" autofocus/>
           <span id="error-userName" class="error"></span>
         </fieldset>
         <fieldset>
           <label for="password" class="strong">
             Password:
           </label>
-          <input type="password" name="password" id="password" value=""/>
+          <input type="password" name="password" id="password" class="form-control" value=""/>
           <span id="error-password" class="error"></span>
         </fieldset>
         <fieldset>
           <label for="fullName" class="strong">Full Name:</label>
-          <input type="text" name="fullName" id="fullName" value=""/>
+          <input type="text" name="fullName" id="fullName" class="form-control" value=""/>
           <span id="error-fullName" class="error"></span>
         </fieldset>
         <fieldset>
           <label for="mailAddress" class="strong">Mail Address:</label>
-          <input type="text" name="mailAddress" id="mailAddress" value=""/>
+          <input type="text" name="mailAddress" id="mailAddress" class="form-control" value=""/>
           <span id="error-mailAddress" class="error"></span>
         </fieldset>
         <fieldset>
           <label for="url" class="strong">URL (optional):</label>
-          <input type="text" name="url" id="url" style="width: 400px;" value=""/>
+          <input type="text" name="url" id="url" class="form-control" value=""/>
           <span id="error-url" class="error"></span>
         </fieldset>
       </div>
diff --git a/src/main/twirl/gitbucket/core/admin/user.scala.html b/src/main/twirl/gitbucket/core/admin/user.scala.html
index 3237545..6723524 100644
--- a/src/main/twirl/gitbucket/core/admin/user.scala.html
+++ b/src/main/twirl/gitbucket/core/admin/user.scala.html
@@ -1,7 +1,8 @@
-@(account: Option[gitbucket.core.model.Account])(implicit context: gitbucket.core.controller.Context)
+@(account: Option[gitbucket.core.model.Account], error: Option[Any] = None)(implicit context: gitbucket.core.controller.Context)
 @import context._
 @html.main(if(account.isEmpty) "New User" else "Update User"){
   @admin.html.menu("users"){
+    @helper.html.error(error)
     <form method="POST" action="@if(account.isEmpty){@path/admin/users/_newuser} else {@path/admin/users/@account.get.userName/_edituser}" validate="true">
       <div class="row">
         <div class="col-md-6">
diff --git a/src/main/twirl/gitbucket/core/admin/usergroup.scala.html b/src/main/twirl/gitbucket/core/admin/usergroup.scala.html
index ac8044d..eaf5a36 100644
--- a/src/main/twirl/gitbucket/core/admin/usergroup.scala.html
+++ b/src/main/twirl/gitbucket/core/admin/usergroup.scala.html
@@ -5,7 +5,7 @@
   @admin.html.menu("users"){
     <form method="POST" action="@if(account.isEmpty){@path/admin/users/_newgroup} else {@path/admin/users/@account.get.userName/_editgroup}" validate="true">
       <div class="row">
-        <div class="col-md-5">
+        <div class="col-md-6">
           <fieldset class="form-group">
             <label for="groupName" class="strong">Group name</label>
             <div>
@@ -31,7 +31,7 @@
             @helper.html.uploadavatar(account)
           </fieldset>
         </div>
-        <div class="col-md-7">
+        <div class="col-md-6">
           <fieldset class="form-group">
             <label class="strong">Members</label>
             <ul id="member-list" class="collaborator">
diff --git a/src/main/twirl/gitbucket/core/signinform.scala.html b/src/main/twirl/gitbucket/core/signinform.scala.html
index bf14229..5b0ff74 100644
--- a/src/main/twirl/gitbucket/core/signinform.scala.html
+++ b/src/main/twirl/gitbucket/core/signinform.scala.html
@@ -1,14 +1,7 @@
 @(systemSettings: gitbucket.core.service.SystemSettingsService.SystemSettings)(implicit context: gitbucket.core.controller.Context)
 @import context._
 <div class="panel panel-default">
-  <div class="panel-heading strong">
-    @if(systemSettings.allowAccountRegistration){
-      <div class="pull-right">
-        <a href="@path/register" class="btn btn-mini">Create new account</a>
-      </div>
-    }
-    Sign in
-  </div>
+  <div class="panel-heading strong">Sign in</div>
   <ul class="list-group list-group-flush">
     <li class="list-group-item">
       <form action="@path/signin" method="POST" validate="true">
@@ -23,6 +16,9 @@
           <input type="password" name="password" id="password" class="form-control"/>
         </div>
         <input type="submit" class="btn btn-success" value="Sign in"/>
+        @if(systemSettings.allowAccountRegistration){
+          or <a href="@path/register">Create new account</a>
+        }
       </form>
     </li>
   </ul>
diff --git a/src/main/webapp/assets/common/css/gitbucket.css b/src/main/webapp/assets/common/css/gitbucket.css
index 32cc167..a2774c1 100644
--- a/src/main/webapp/assets/common/css/gitbucket.css
+++ b/src/main/webapp/assets/common/css/gitbucket.css
@@ -316,6 +316,11 @@
   margin-bottom: 0px;
 }
 
+div.row {
+  margin-left: 0px;
+  margin-right: 0px;
+}
+
 ul.nav-tabs {
   height: 42px;
 }