diff --git a/lib/peter/strategies/admin.rb b/lib/peter/strategies/admin.rb
index fe6d0a5..829a078 100644
--- a/lib/peter/strategies/admin.rb
+++ b/lib/peter/strategies/admin.rb
@@ -1,17 +1,17 @@
 Warden::Strategies.add(:admin) do
   def valid?
     params['username'] && params['password']
   end
 
   def authenticate!
     admin = User.fetch_admin_with_password(params['username'], params['password'])
 
     return fail!("Wrong credentials") unless admin
-    return fail!("Service not available") unless admin.enabled?
+    return fail!("Your account is disabled") unless admin.enabled?
 
     admin.login_at = Time.now
     admin.save
 
     success!(admin)
   end
 end
diff --git a/lib/peter/strategies/institutional.rb b/lib/peter/strategies/institutional.rb
index d234cb2..f8780a2 100644
--- a/lib/peter/strategies/institutional.rb
+++ b/lib/peter/strategies/institutional.rb
@@ -1,39 +1,39 @@
 Warden::Strategies.add(:institutional) do
   def valid?
     fetch_header('HTTP_REMOTE_USER').present? &&
       fetch_header('HTTP_MAIL').present? &&
       fetch_header('HTTP_ENTITLEMENT').present? &&
       fetch_header('HTTP_ENTITLEMENT').include?('urn:mace:grnet.gr:archiving:admin')
   end
 
   def fetch_header(header)
     request.env[header]
   end
 
   def authenticate!
     Rails.logger.warn("WARDEN: INFO institutional has valid headers")
     if !Archiving.settings[:institutional_authentication_enabled]
       return fail!("Shibboleth is temporarily disabled")
     end
 
     identifier = "institutional:#{fetch_header("HTTP_REMOTE_USER")}"
     user = User.find_or_initialize_by(identifier: identifier)
 
     return fail!("Wrong credentials") unless user
 
     user.login_at = Time.now
 
     if user.new_record?
       user.email = fetch_header("HTTP_MAIL")
       user.username = fetch_header("HTTP_MAIL")
       user.enabled = true
       user.institutional!
     else
       user.save
     end
 
-    return fail!("Service not available") unless user.enabled?
+    return fail!("Your account is disabled") unless user.enabled?
 
     success!(user)
   end
 end
diff --git a/lib/peter/strategies/vima.rb b/lib/peter/strategies/vima.rb
index b53d230..a038cf1 100644
--- a/lib/peter/strategies/vima.rb
+++ b/lib/peter/strategies/vima.rb
@@ -1,123 +1,123 @@
 ## -*- encoding : utf-8 -*-
 require 'oauth2'
 
 Warden::Strategies.add(:vima) do
   Key = Rails.application.secrets.oauth2_vima_client_id
   Secret = Rails.application.secrets.oauth2_vima_secret
 
   def valid?
     params['vima'] || params['error'] || params['code']
   end
 
   def client
     OAuth2::Client.new(
       Key,
       Secret,
       site: 'https://vima.grnet.gr',
       token_url: "/o/token",
       authorize_url: "/o/authorize",
       :ssl => {:ca_path => "/etc/ssl/certs"}
     )
   end
 
   def redirect_uri
     uri = URI.parse(request.url)
     uri.scheme = 'https' unless Rails.env.development?
     uri.path = '/vima'
     uri.query = nil
     uri.to_s
   end
 
   def redirect_to_vima
     redirect! client.auth_code.authorize_url(:redirect_uri => redirect_uri, scope: 'read')
   end
 
   def authenticate!
     if !Archiving::settings[:vima_oauth_enabled]
       return fail!("ViMa is temporarily disabled")
     end
 
     if params['error']
       Rails.logger.warn("WARDEN: ERROR #{params['error']}")
       return fail!("ViMa log in failed: #{params['error']}")
     end
 
     return redirect_to_vima if params['vima']
 
     access_token = client.auth_code.get_token(
       params['code'],
       { :redirect_uri => redirect_uri },
       { :mode => :query, :param_name => "access_token", :header_format => "" })
 
     user_data = access_token.get(
       'https://vima.grnet.gr/user/details',
       { mode: :query, param_name: 'access_token' }
     ).parsed.deep_symbolize_keys
 
     if [user_data[:username], user_data[:email], user_data[:id]].any?(&:blank?)
       return fail!("ViMa login failed: no user data")
     end
 
     ###### TBR
     # temporary, for user migration
     user = User.find_or_initialize_by(username: user_data[:username],
                                       email: user_data[:email])
     user.identifier = "vima:#{user_data[:id]}"
     ######
 
     # actual implementation
     #user = User.find_or_initialize_by(identifier: user_data[:identifier])
 
     if !user.enabled? && user.persisted?
-      return fail!('Service not available')
+      return fail!('Your account is disabled')
     end
 
     user.login_at = Time.now
 
     if user.new_record?
       user.enabled = true
       # TBR
       user.identifier = "vima:#{user_data[:id]}"
       user.vima!
     else
       user.save!
     end
 
     if user.refetch_hosts?
       vms = fetch_vms(access_token)[:response][:instances]
       user.hosts_updated_at = Time.now
       user.temp_hosts = vms
       user.save
     end
 
     vms ||= (user.temp_hosts + user.hosts.pluck(:fqdn)).uniq
 
     assign_vms(user, vms)
 
     success!(user)
   end
 
   def fetch_vms(access_token)
     Rails.logger.warn("ViMa: fetching vms")
     vms = access_token.get(
       'https://vima.grnet.gr/instances/list?tag=vima:service:archiving',
       { mode: :query, param_name: 'access_token' }
     ).parsed.deep_symbolize_keys
 
     if vms[:response][:errors] != false
       Rails.logger.warn("ViMa: errors on instances/list response for user #{vms[:user][:username]}")
     end
 
     vms
   end
 
   def assign_vms(user, vms)
     Rails.logger.warn("ViMa: user: #{user.username}")
     Rails.logger.warn("ViMa: vms: #{vms}")
     Rails.logger.warn("ViMa: session vms: #{session[:vms]}")
     session[:vms] = vms.first(50)
     Host.where(fqdn: vms).each do |host|
       host.users << user unless host.users.include?(user)
     end
   end
 end