Answers.Body: <p>I was also dealing with the same problem and after many debugging, the following uninstall script finally helped me to install CiviVolunteer succesfully. Warning: you will lose the data stored in CiviVolunteer tables. Use at own risk.</p>
  
  <pre><code>/* drop custom tables */
  DROP TABLE IF EXISTS `civicrm_volunteer_need`;
  DROP TABLE IF EXISTS `civicrm_volunteer_project_contact`;
  DROP TABLE IF EXISTS `civicrm_volunteer_project`;
  
  /* drop report-related records */
  DELETE FROM `civicrm_report_instance` WHERE report_id = 'volunteer';
  
  /* drop custom option group for roles (FK takes care of option values) */
  DELETE FROM `civicrm_option_group` WHERE NAME = 'volunteer_role';
  DELETE FROM `civicrm_option_group` WHERE NAME = 'skill_level';
  
  /* drop custom field group from Activities (FK takes care of fields) */
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'CiviVolunteer';
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'Volunteer_Information';
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'volunteer_commendation';
  
  DELETE FROM civicrm_option_group WHERE `name` = 'msg_tpl_workflow_volunteer';
  DELETE FROM civicrm_option_group WHERE `name` = 'volunteer_project_relationship';
  DELETE FROM civicrm_contact_type WHERE `name` = 'Volunteer';
  DELETE FROM civicrm_custom_group WHERE civicrm_custom_group.name = 'CiviVolunteer'; 
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Volunteer_Need_Id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Volunteer_Role_Id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Time_Scheduled_Minutes';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Time_Completed_Minutes';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'volunteer_project_id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'camera_skill_level';
  DELETE FROM civicrm_msg_template WHERE msg_title = 'Volunteer - Registration (on-line)';
  DELETE FROM civicrm_navigation WHERE `name` = 'New Volunteer';
  DELETE FROM civicrm_option_value WHERE `label` = 'Volunteer';
  DELETE FROM civicrm_option_value WHERE `label` = 'Volunteer Commendation';
  DELETE civicrm_uf_join FROM civicrm_uf_group JOIN civicrm_uf_join ON civicrm_uf_join.uf_group_id = civicrm_uf_group.id  WHERE `group_type` = 'Volunteer,Contact';
  DELETE FROM civicrm_uf_group WHERE `group_type` = 'Volunteer,Contact';
  
  /* relationship_type, */
  
  
  /* drop volunteer sign-up profile (FK takes care of profile fields) */
  DELETE FROM `civicrm_uf_join` WHERE `module` = 'CiviVolunteer';
  DELETE FROM `civicrm_uf_group` WHERE `name` = 'volunteer_sign_up';
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-06T20:57:55.433Z
Answers.Text: I used this and still get error `name` must be unique. An conflicting entity already exists - id: 354
Answers.UserDisplayName: Zachary
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-10-26T09:29:00.523Z
Answers.LastActivityDate: 2018-10-26T09:29:00.523Z
Answers.UserDisplayName: advw
Answers.Body: <p>The multiple installs (and I'm guessing not always clean uninstall) of the CiviVolunteer module have most certainly corrupted your database and left some files behind that produce these messages (these look like debug messages left by the developer in a not-yet-final version).</p>
  
  <p>Since you have no data in CiviVolunteer I would:</p>
  
  <ul>
  <li>disable, then uninstall the CiviVolunteer extension from the GUI,</li>
  <li>if this produces errors, or just for safety, go in the database and execute the following file: <a href="https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql" rel="nofollow">https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql</a>, then execute: DELETE FROM civicrm_extension WHERE full_name = 'org.civicrm.volunteer';</li>
  <li>clear all caches in CiviCRM (Administer >> System Settings >> Cleanup Caches and Update Path)</li>
  <li>delete the org.civicrm.volunteer folder in your extensions directory</li>
  <li>download the latest <strong>released</strong> version of the extension that supports your version of CiviCRM, and go through the install process again</li>
  </ul>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-30T18:01:12.897Z
Answers.Text: for whatever it is worth - I have not been able to install CiviVolunteer with an  in-use CiviCRM install. I have been able to install it on a blank install of Wordpress 4.6 and CiviCRM 4.7.10 but only after I went through the site and database and removed any references to the word 'volunteer'. I still got two errors on the install, but it did install and it is working as far as I can tell. I will be putting it through its paces over the next couple of weeks as a trial.
Answers.UserDisplayName: Barbara Forbes-Lyons
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-06-23T04:11:32.573Z
Answers.LastActivityDate: 2016-06-23T04:11:32.573Z
Answers.UserDisplayName: cividesk
Answers.Body: <p>I had the same trouble. That was a nightmare.</p>
  
  <p>Finally I got through with this command :</p>
  
  <p><a href="https://domainURL/civicrm/admin/extensions?action=disable&amp;id=org.civicrm.volunteer&amp;key=org.civicrm.volunteer" rel="nofollow noreferrer">https://domainURL/civicrm/admin/extensions?action=disable&amp;id=org.civicrm.volunteer&amp;key=org.civicrm.volunteer</a></p>
  
  <p>But still there is several tables that need to be remove manually in the SQL database :
  civicrm_value_civivolunteer_2
  civicrm_value_volunteer_com_4
  civicrm_value_volunteer_inf_3
  civicrm_volunteer_need
  civicrm_volunteer_project
  civicrm_volunteer_project_contact</p>
  
  <p>but after reinstall there is an error :</p>
  
  <blockquote>
    <p><code>CiviCRM_API3_Exception: "Field:</code>name<code>must be unique. An conflicting entity already exists - id: 108"</code></p>
  </blockquote>
  
  <p>So I remove manually from civicrm_custom_group  and civicrm_custom_field  for everything with volunteer :</p>
  
  <blockquote>
    <p>DELETE FROM <code>civicrm_custom_group</code> WHERE <code>civicrm_custom_group</code>.<code>id</code> = 2;
    DELETE FROM <code>civicrm_custom_field</code> WHERE <code>civicrm_custom_field</code>.<code>id</code> = 2;</p>
  </blockquote>
  
  <p>But still when reinstall the extension I still have an error.</p>
  
  <blockquote>
    <p>CiviCRM_API3_Exception: "Field: <code>name</code> must be unique. An conflicting
    entity already exists - id: 108"</p>
  </blockquote>
  
  <p>Then I found this 
  <a href="https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql" rel="nofollow noreferrer">https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql</a></p>
  
  <p>But no luck still. Error.</p>
  
  <p>So I give up. I will not use this extension that leave too much legacy.
  I remove it from the ext folder to avoid installing again.</p>
  
  <p>////// EDIT //////</p>
  
  <p>Finally, as there there were no way to avoid countless errors indicating Volunteer. I decided to try reinstall it rather than suppress it.
  That wasn't possible. So I compare a fresh install of CiviCRM with Volunteer. 
  First I copy these tables (all are empty) via phpmyadmin, or in one case I changed the name to match :
  <a href="https://i.sstatic.net/cI0w4.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/cI0w4.png" alt="Missing tables"></a></p>
  
  <p>Then I enter the SQL line :</p>
  
  <blockquote>
    <p>INSERT INTO <code>civicrm_extension</code> ( <code>type</code>, <code>full_name</code>, <code>name</code>, <code>label</code>, <code>file</code>, <code>schema_version</code>, <code>is_active</code>) VALUES
    ( 'module', 'org.civicrm.volunteer', 'CiviVolunteer', 'CiviVolunteer', 'volunteer', NULL , 1);</p>
  </blockquote>
  
  <p>Then Volunteer worked. Happy !</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-05-27T04:37:09.587Z
Answers.Text: Thank you for this summary. It may not qualify as an Answer but I am going to give it a +1 as i think it provides useful notes / warnings for others
Answers.UserDisplayName: petednz - fuzion
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-05-26T12:36:41.187Z
Answers.LastActivityDate: 2018-06-10T13:11:39.460Z
Answers.LastEditDate: 2018-06-10T13:11:39.460Z
Answers.UserDisplayName: Ichi
Answers.Body: <p>Is missing in volunteer_uninstall.sql:</p>
  
  <p>DELETE FROM <code>civicrm_option_group</code> WHERE <code>name</code> = 'skill_level';</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-08T22:20:36.240Z
Answers.LastActivityDate: 2020-01-08T22:20:36.240Z
Answers.UserDisplayName: Voyceik
Body: <p>Failure installing CiviVolunteer ver 4.6-2.1.1 on CiviCRM ver 4.7.6.</p>
  
  <h2>I'd previously had CiviVolunteer1.4, (pretty much just playing with it) then attempted 2.0 install several weeks ago.  Nothing happened, and then learned that it was incompatible with 4.7.   Newest release was supposed to fix, but, on attempting install -> I'm getting: message:</h2>
  
  <p>Sorry but we are not able to provide this at the moment.
     Field: <code>name</code> must be unique. An conflicting entity already exists - id: 104</p>
  
  <h2>   Return to home page.</h2>
  
  <p>On return to Civi dashboard, lots of msgs get displayed for just a few sec re: found title, found field name...
  <a href="https://i.sstatic.net/Zy2Ga.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Zy2Ga.png" alt="Messages"></a>
  Also including image of extensions screen, if that's interesting...
  <a href="https://i.sstatic.net/QaNUp.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/QaNUp.png" alt="Extensions Page"></a></p>
  
  <p>Thanks!</p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-06-30T14:33:51.147Z
Comments.Text: I encountered this issue today. Check your custom fields for any groups or fields with Volunteer in the name.
Comments.UserDisplayName: Tommy B
Tags: <installation><civivolunteer><failure>
Title: CiviVolunteer install fails
ThreadText: # CiviVolunteer install fails
  
  (Asked by: username_0 on 2016-06-14)
  
  Failure installing CiviVolunteer ver 4.6-2.1.1 on CiviCRM ver 4.7.6.
  
  ## I'd previously had CiviVolunteer1.4, (pretty much just playing with it) then attempted 2.0 install several weeks ago. Nothing happened, and then learned that it was incompatible with 4.7. Newest release was supposed to fix, but, on attempting install -> I'm getting: message:
  
  Sorry but we are not able to provide this at the moment.
  Field: `name` must be unique. An conflicting entity already exists - id: 104
  
  ## Return to home page.
  
  On return to Civi dashboard, lots of msgs get displayed for just a few sec re: found title, found field name...
  [![Messages](https://i.sstatic.net/Zy2Ga.png)](https://i.sstatic.net/Zy2Ga.png)
  Also including image of extensions screen, if that's interesting...
  [![Extensions Page](https://i.sstatic.net/QaNUp.png)](https://i.sstatic.net/QaNUp.png)
  
  Thanks!
  
  **Tags:** installation, civivolunteer, failure
  
  > **Comments:**
  > **username_1**: I encountered this issue today. Check your custom fields for any groups or fields with Volunteer in the name.  
  
  ---
  
  ## 4 answers
  
  ### Answer by username_2 on 2018-10-26. Score: 4
  
  I was also dealing with the same problem and after many debugging, the following uninstall script finally helped me to install CiviVolunteer succesfully. Warning: you will lose the data stored in CiviVolunteer tables. Use at own risk.
  /* drop custom tables */
  DROP TABLE IF EXISTS `civicrm_volunteer_need`;
  DROP TABLE IF EXISTS `civicrm_volunteer_project_contact`;
  DROP TABLE IF EXISTS `civicrm_volunteer_project`;
  
  /* drop report-related records */
  DELETE FROM `civicrm_report_instance` WHERE report_id = 'volunteer';
  
  /* drop custom option group for roles (FK takes care of option values) */
  DELETE FROM `civicrm_option_group` WHERE NAME = 'volunteer_role';
  DELETE FROM `civicrm_option_group` WHERE NAME = 'skill_level';
  
  /* drop custom field group from Activities (FK takes care of fields) */
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'CiviVolunteer';
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'Volunteer_Information';
  DELETE FROM `civicrm_custom_group` WHERE `name` = 'volunteer_commendation';
  
  DELETE FROM civicrm_option_group WHERE `name` = 'msg_tpl_workflow_volunteer';
  DELETE FROM civicrm_option_group WHERE `name` = 'volunteer_project_relationship';
  DELETE FROM civicrm_contact_type WHERE `name` = 'Volunteer';
  DELETE FROM civicrm_custom_group WHERE civicrm_custom_group.name = 'CiviVolunteer'; 
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Volunteer_Need_Id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Volunteer_Role_Id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Time_Scheduled_Minutes';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'Time_Completed_Minutes';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'volunteer_project_id';
  DELETE FROM civicrm_custom_field WHERE civicrm_custom_field.name = 'camera_skill_level';
  DELETE FROM civicrm_msg_template WHERE msg_title = 'Volunteer - Registration (on-line)';
  DELETE FROM civicrm_navigation WHERE `name` = 'New Volunteer';
  DELETE FROM civicrm_option_value WHERE `label` = 'Volunteer';
  DELETE FROM civicrm_option_value WHERE `label` = 'Volunteer Commendation';
  DELETE civicrm_uf_join FROM civicrm_uf_group JOIN civicrm_uf_join ON civicrm_uf_join.uf_group_id = civicrm_uf_group.id  WHERE `group_type` = 'Volunteer,Contact';
  DELETE FROM civicrm_uf_group WHERE `group_type` = 'Volunteer,Contact';
  
  /* relationship_type, */
  
  
  /* drop volunteer sign-up profile (FK takes care of profile fields) */
  DELETE FROM `civicrm_uf_join` WHERE `module` = 'CiviVolunteer';
  DELETE FROM `civicrm_uf_group` WHERE `name` = 'volunteer_sign_up';
  
  > **Comments:**
  > **username_3**: I used this and still get error `name` must be unique. An conflicting entity already exists - id: 354  
  
  ---
  
  ### Answer by username_4 on 2016-06-23. Score: 2
  
  The multiple installs (and I'm guessing not always clean uninstall) of the CiviVolunteer module have most certainly corrupted your database and left some files behind that produce these messages (these look like debug messages left by the developer in a not-yet-final version).
  
  Since you have no data in CiviVolunteer I would:
  
  * disable, then uninstall the CiviVolunteer extension from the GUI,
  * if this produces errors, or just for safety, go in the database and execute the following file: <https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql>, then execute: DELETE FROM civicrm\_extension WHERE full\_name = 'org.civicrm.volunteer';
  * clear all caches in CiviCRM (Administer >> System Settings >> Cleanup Caches and Update Path)
  * delete the org.civicrm.volunteer folder in your extensions directory
  * download the latest **released** version of the extension that supports your version of CiviCRM, and go through the install process again
  
  > **Comments:**
  > **username_5**: for whatever it is worth - I have not been able to install CiviVolunteer with an  in-use CiviCRM install. I have been able to install it on a blank install of Wordpress 4.6 and CiviCRM 4.7.10 but only after I went through the site and database and removed any references to the word 'volunteer'. I still got two errors on the install, but it did install and it is working as far as I can tell. I will be putting it through its paces over the next couple of weeks as a trial.  
  
  ---
  
  ### Answer by username_6 on 2018-05-26. Score: 1
  
  I had the same trouble. That was a nightmare.
  
  Finally I got through with this command :
  
  <https://domainURL/civicrm/admin/extensions?action=disable&id=org.civicrm.volunteer&key=org.civicrm.volunteer>
  
  But still there is several tables that need to be remove manually in the SQL database :
  civicrm\_value\_civivolunteer\_2
  civicrm\_value\_volunteer\_com\_4
  civicrm\_value\_volunteer\_inf\_3
  civicrm\_volunteer\_need
  civicrm\_volunteer\_project
  civicrm\_volunteer\_project\_contact
  
  but after reinstall there is an error :
  
  > `CiviCRM_API3_Exception: "Field:`name`must be unique. An conflicting entity already exists - id: 108"`
  
  So I remove manually from civicrm\_custom\_group and civicrm\_custom\_field for everything with volunteer :
  
  > DELETE FROM `civicrm_custom_group` WHERE `civicrm_custom_group`.`id` = 2;
  > DELETE FROM `civicrm_custom_field` WHERE `civicrm_custom_field`.`id` = 2;
  
  But still when reinstall the extension I still have an error.
  
  > CiviCRM\_API3\_Exception: "Field: `name` must be unique. An conflicting
  > entity already exists - id: 108"
  
  Then I found this
  <https://github.com/civicrm/org.civicrm.volunteer/blob/master/sql/volunteer_uninstall.sql>
  
  But no luck still. Error.
  
  So I give up. I will not use this extension that leave too much legacy.
  I remove it from the ext folder to avoid installing again.
  
  ////// EDIT //////
  
  Finally, as there there were no way to avoid countless errors indicating Volunteer. I decided to try reinstall it rather than suppress it.
  That wasn't possible. So I compare a fresh install of CiviCRM with Volunteer.
  First I copy these tables (all are empty) via phpmyadmin, or in one case I changed the name to match :
  [![Missing tables](https://i.sstatic.net/cI0w4.png)](https://i.sstatic.net/cI0w4.png)
  
  Then I enter the SQL line :
  
  > INSERT INTO `civicrm_extension` ( `type`, `full_name`, `name`, `label`, `file`, `schema_version`, `is_active`) VALUES
  > ( 'module', 'org.civicrm.volunteer', 'CiviVolunteer', 'CiviVolunteer', 'volunteer', NULL , 1);
  
  Then Volunteer worked. Happy !
  
  > **Comments:**
  > **username_7**: Thank you for this summary. It may not qualify as an Answer but I am going to give it a +1 as i think it provides useful notes / warnings for others  
  
  ---
  
  ### Answer by username_8 on 2020-01-08. Score: 0
  
  Is missing in volunteer\_uninstall.sql:
  
  DELETE FROM `civicrm_option_group` WHERE `name` = 'skill\_level';
  
  
  ---
  
  