Trying to populate a database with some users using rake db:populate.

But im getting this error trace:

** Invoke db:populate (first_time)
** Invoke db:populate:accounts (first_time)
** Invoke db:populate:setup (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:populate:setup
** Execute db:populate:accounts
[populate] accounts
rake aborted!
Validation failed: Logo failed to be processed.
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/validations.rb:1090:in
`save_without_dirty!'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/dirty.rb:87:in
`save_without_transactions!'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:200:in
`save!'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in
`transaction'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:182:in
`transaction'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:200:in
`save!'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:208:in
`rollback_active_record_state!'
/home/andersnguyen/.gem/ruby/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:200:in
`save!'
/usr/lib/ruby/gems/1.8/gems/machinist-1.0.6/lib/machinist/active_record.rb:55:in
`make'
/home/andersnguyen/rubyprojects/mediapilot/lib/tasks/populate.rake:35
/usr/lib/ruby/1.8/rake.rb:636:in `call'
/usr/lib/ruby/1.8/rake.rb:636:in `execute'
/usr/lib/ruby/1.8/rake.rb:631:in `each'
/usr/lib/ruby/1.8/rake.rb:631:in `execute'
/usr/lib/ruby/1.8/rake.rb:597:in `invoke_with_call_chain'
/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
/usr/lib/ruby/1.8/rake.rb:590:in `invoke_with_call_chain'
/usr/lib/ruby/1.8/rake.rb:607:in `invoke_prerequisites'
/usr/lib/ruby/1.8/rake.rb:604:in `each'
/usr/lib/ruby/1.8/rake.rb:604:in `invoke_prerequisites'
/usr/lib/ruby/1.8/rake.rb:596:in `invoke_with_call_chain'
/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
/usr/lib/ruby/1.8/rake.rb:590:in `invoke_with_call_chain'
/usr/lib/ruby/1.8/rake.rb:583:in `invoke'
/usr/lib/ruby/1.8/rake.rb:2051:in `invoke_task'
/usr/lib/ruby/1.8/rake.rb:2029:in `top_level'
/usr/lib/ruby/1.8/rake.rb:2029:in `each'
/usr/lib/ruby/1.8/rake.rb:2029:in `top_level'
/usr/lib/ruby/1.8/rake.rb:2068:in `standard_exception_handling'
/usr/lib/ruby/1.8/rake.rb:2023:in `top_level'
/usr/lib/ruby/1.8/rake.rb:2001:in `run'
/usr/lib/ruby/1.8/rake.rb:2068:in `standard_exception_handling'
/usr/lib/ruby/1.8/rake.rb:1998:in `run'
/usr/bin/rake:28



here is the populate.db file:

# encoding: utf-8

class Range
  def random
    rand(last - first + 1) + first
  end
end

namespace :db do

  desc "Erase and fill database"
  task :populate => [
    'db:populate:accounts',
    'db:populate:users',
    'db:populate:memberships',
    'db:populate:feeds',
    'db:populate:events',
    'db:populate:sources',
    'db:populate:editorials',
    'db:populate:social_posts',
    'db:populate:variables',
    'db:populate:statistics',
    'feed:retrieve'
  ]

  namespace :populate do

    task :setup => :environment do
      require File.join(Rails.root, 'spec', 'blueprints')
    end

    task :accounts => 'db:populate:setup' do
      puts "[populate] accounts"
      Account.delete_all
      Account.make(:name => 'SJ', :logo =>
File.open(Rails.root.join('features/fixtures/logo-sj.png')))
      Account.make(:name => 'Telia', :logo =>
File.open(Rails.root.join('features/fixtures/logo-telia.png')))
      Account.make(:name => 'Stena Line', :logo =>
File.open(Rails.root.join('features/fixtures/logo-stena.png')))
      Account.make(:name => 'Max', :logo =>
File.open(Rails.root.join('features/fixtures/logo-max.png')))
      Account.make(:name => 'Coop', :logo =>
File.open(Rails.root.join('features/fixtures/logo-coop.png')))
    end

    task :users => 'db:populate:setup' do
      puts "[populate] users"
      User.delete_all
      User.make(:password => 'test1234', :email => "admin / elabs.se",
:role => 'admin', :locale => "en")
      User.make(:password => 'test1234', :email => "analyst / elabs.se",
:role => 'analyst', :locale => "en")
      User.make(:password => 'test1234', :email => "customer / elabs.se",
:role => 'customer', :locale => "en")
      User.make(:password => 'test1234', :email => "swedish / elabs.se",
:role => 'admin', :locale => "sv")
      12.times { User.make(:role => (User::ROLES - ['Admin']).rand) }
    end

    task :memberships => 'db:populate:setup' do
      puts "[populate] memberships"
      Membership.delete_all
     User.find(:all, :conditions => "role != 'Admin'").each do | userf user.customer?
          user.accounts << Account.random
        else
          (1..4).random.times { user.accounts << Account.random }
        end
      end
    end

    task :sources => 'db:populate:setup' do
      puts "[populate] sources"
      Source.delete_all
      Source.make(:name => 'Aftonbladet', :circulation => 1_232_432,
:category => 'popular')
      Source.make(:name => 'DN', :circulation => 1_632_653, :category3D>
'large_city')
      Source.make(:name => 'Expressen', :circulation => 823_583,
:category => 'popular')
      Source.make(:name => 'Göteborgs-Posten', :circulation => 442_556,
:category => 'large_city')
      Source.make(:name => 'Sydsvenska Dagbladet', :circulation =>
350_834, :category => 'local')
      Source.make(:name => 'Dagens Industri', :circulation => 2_342_342,
:category => 'trade')
      Source.make(:name => 'Engadget', :circulation => 7_234_618,
:category => 'trade')
      Source.make(:name => 'Tech Crunch', :circulation => 13_546_245,category => 'trade')
      Source.make(:name => 'Wired', :circulation => 1_350_000, :category
=> 'trade')
    end

    task :feeds => 'db:populate:setup' do
      puts "[populate] feeds"
      Feed.delete_all

     Account.all.each do | account |
        [
          ['http://www.dn.se/m/rss/toppnyheter', "DN.se toppnyheter"],
          ['http://www.gp.se/1.16943', 'Göteborgsposten'],
          ['http://www.aftonbladet.se/sportbladet/rss.xml', 'Aftonbladet
sportnyheter'],
          ['http://www.sr.se/rssfeed/rssfeed.aspx?rssfeed=83&format=1',
'Sveriges Radio EKOT']
       ].each do | url, name |
           account.feeds.make(:name => name, :url => url, :category =>
'editorial')
        end
        [
          ['http://twitter.com/statuses/user_timeline/17023971.rss',
"eLabs on Twitter", false],
          ['http://twitter.com/statuses/user_timeline/23775395.rss',
'MediaPilot on Twitter', false],
          ['http://friendfeed.com/cjkihlbom?format=atom', 'CJ Kihlbom on
FriendFeed', true],
          ['http://feeds.digg.com/digg/upcoming.rss', 'Fresh stuff on
Digg', true]
       ].each do | url, name, preview |
           account.feeds.make(:name => name, :url => url, :category =>
'social', :preview => preview)
        end
      end
    end

    task :events => 'db:populate:setup' do
      puts "[populate] events"
      Event.delete_all
     Account.all.each do | account |
        (10..15).random.times { Event.make(:account => account) }
      end
    end

    task :editorials => 'db:populate:setup' do
      puts "[populate] editorials"
      Editorial.delete_all
      Account.all.each do | account |
        (60..100).random.times { Editorial.make(:printed, :account =>
account, :event => account.events.random, :source => Source.random) }ccount.editorial_feed_items.each do | item |
          Editorial.make(:web, :account => account, :feed_item => item,
:url => item.url, :headline => item.title, :event =>
account.events.random, :source => Source.random) if(rand(2).zero?)
        end
      end
    end

    task :social_posts => 'db:populate:setup' do
      puts "[populate] social_posts"
      SocialPost.delete_all
     Account.all.each do               | account |
     account.social_feed_items.each do | item    |
          SocialPost.make(:account => account, :feed_item => item,
:headline => item.title) if(rand(2).zero?)
        end
      end
    end

    task :variables => 'db:populate:setup' do
      puts "[populate] custom variables"
      Variable.delete_all
      VariableOption.delete_all
      EditorialVariableOption.delete_all
      SocialPostVariableOption.delete_all
     Account.all.each do | account |
        products = account.variables.make(:name => 'Products',
:multiple_choice => true, :category => 'editorial')
       %w(Fanta Sprite Cola).each do | option_name |
          products.options.make(:name => option_name)
        end
        flavors = account.variables.make(:name => 'Flavors',
:multiple_choice => false, :category => 'editorial')
       %w(Sweet Sour Bitter Salty).each do | option_name |
          flavors.options.make(:name => option_name)
        end
        sugar_content = account.variables.make(:name => 'Sugar Content',
:multiple_choice => false, :category => 'social')
       %w(Diabetes High Medium Low).each do | option_name |
          sugar_content.options.make(:name => option_name)
        end

        product_options = products.options
        flavor_options  = flavors.options
       account.editorials.each do | editorial |
          editorial.variable_options.push(*product_options.shuffle[0,rand(4)])
          editorial.variable_options.push(flavor_options.rand)
        end

        sugar_content_options = sugar_content.options
       account.social_posts.each do | social_post |
          social_post.variable_options.push(sugar_content_options.rand)
        end

      end

    end

    task :statistics => 'db:populate:setup' do
      puts '[populate] statistics'
      Statistic.delete_all
     Account.all.each do | account |
        account.statistics.make(:pie, :category => 'editorial', :name =>
'Favorability Overview', :group_parameter_one_type => 'favorability')
        account.statistics.make(:bar, :category => 'editorial', :name =>
'Media types', :group_parameter_one_type => 'medium',
:group_parameter_two_type => nil)
        sugar_content = account.variables.find_by_name('Sugar Content')ccount.statistics.make(:bar, :category => 'social', :name =>Sugar content per favorability', :group_parameter_one_type =>
"variable_#{sugar_content.id}", :group_parameter_two_type =>
'favorability')
        account.statistics.make(:line, :category => 'social', :name =>
'Development of Comments', :group_parameter_one_type => 'time_months',
:group_parameter_two_type => 'comments')
      end
    end
  end

end