Error during uninstall

[uart-aplex]

It seems conflicted when uninstall KM:

rake redmine:plugins:migrate NAME=redmine_knowledgebase VERSION=0 RAILS_ENV=production
== 20150616103300 ChangeColumnArticleToLongText: reverting ====================
== 20150616103300 ChangeColumnArticleToLongText: reverted (0.0000s) ===========

== 20150326093139 AddMissingTaggableIndex: reverting ==========================
== 20150326093139 AddMissingTaggableIndex: reverted (0.0000s) =================

== 20150326093122 AddTaggingsCounterCacheToTags: reverting ====================
-- remove_column(:tags, :taggings_count)
rake aborted!
StandardError: An error has occurred, all later migrations canceled:

Mysql2::Error: Can't DROP 'taggings_count'; check that column/key exists: ALTER TABLE tags DROP COLUMN taggings_count
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/plugins/redmine_knowledgebase/db/migrate/20150326093122_add_taggings_counter_cache_to_tags.rb:14:in down' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:520:in down'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:542:in migrate_plugin' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:483:in migrate'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:494:in migrate' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/tasks/redmine.rake:135:in block (3 levels) in <top (required)>'

Caused by:
ActiveRecord::StatementInvalid: Mysql2::Error: Can't DROP 'taggings_count'; check that column/key exists: ALTER TABLE tags DROP COLUMN taggings_count
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/plugins/redmine_knowledgebase/db/migrate/20150326093122_add_taggings_counter_cache_to_tags.rb:14:in down' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:520:in down'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:542:in migrate_plugin' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:483:in migrate'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:494:in migrate' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/tasks/redmine.rake:135:in block (3 levels) in <top (required)>'

Caused by:
Mysql2::Error: Can't DROP 'taggings_count'; check that column/key exists
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/plugins/redmine_knowledgebase/db/migrate/20150326093122_add_taggings_counter_cache_to_tags.rb:14:in down' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:520:in down'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:542:in migrate_plugin' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:483:in migrate'
/home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/redmine/plugin.rb:494:in migrate' /home/aplex/redmine-4.1.1-3/apps/redmine/htdocs/lib/tasks/redmine.rake:135:in block (3 levels) in <top (required)>'
Tasks: TOP => redmine:plugins:migrate
(See full trace by running task with --trace)