Answers.Body: <p>These smart groups include custom fields that no longer exist.  In the first case, it's the custom field with id of 52; in the second the id is 21.  These smart groups should have their criteria modified to reflect the fact that these groups no longer exist.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-02T10:28:17.040Z
Answers.Text: How can I do it, if the standard way - **Edit Smart Group Criteria** - produces the same error?
Answers.UserDisplayName: Aivars
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-02T08:21:38.617Z
Answers.LastActivityDate: 2019-03-02T08:21:38.617Z
Answers.UserDisplayName: Jon G - Megaphone Tech
Answers.Body: <p>@junglebird on <a href="https://chat.civicrm.org/civicrm" rel="nofollow noreferrer">https://chat.civicrm.org/civicrm</a> provided a solution to delete such groups via API Explorer.</p>
  
  <p>Smart groups also have an entry in <strong>civicrm_saved_search</strong>.  I think it would be safer to make a list of the group IDs, go to <strong>Support >> Developer >> API Explorer</strong> and select Entity of <strong>Group</strong>, Action of <strong>Delete</strong>, and set the ID accordingly.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-04-01T15:42:01.583Z
Answers.Text: This is me - I should try harder to consolidate my CiviCRM usernames :)
Answers.UserDisplayName: Jon G - Megaphone Tech
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-03-29T12:19:29.360Z
Answers.LastActivityDate: 2019-03-29T12:19:29.360Z
Answers.UserDisplayName: Aivars
Body: <p>When I try to open <strong>Contacts</strong> of some Smart Groups, CiviCRM gives me error:</p>
  
  <p><strong>Expected one CustomField but found 0</strong></p>
  
  <p><a href="https://i.sstatic.net/29dxs.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/29dxs.png" alt="enter image description here"></a></p>
  
  <p>All parent Smart Groups that include faulty Smart Groups are also rendering the same error (can't open contacts).</p>
  
  <p>If I try to delete these Smart Groups, I get Network Error.
  <a href="https://i.sstatic.net/SJmOt.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/SJmOt.png" alt="enter image description here"></a></p>
  
  <p>When in <strong>Groups tab of Contact profile</strong> I open Smart Groups subsection, it remains empty (no Smart groups are listed). Not sure if for all contacts or only those that are included in faulty smart groups.</p>
  
  <p>How can I fix this error?</p>
  
  <p>CiviCRM 4.7.14 on Drupal 7.59</p>
  
  <h1>DEBUG INFO (sample 1)</h1>
  
  <p>CiviCRM_API3_Exception: "Expected one CustomField but found 0"</p>
  
  <pre><code>#0 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4491): civicrm_api3("CustomField", "getvalue", (Array:3))
  #1 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(452): CRM_Contact_BAO_Query::isCustomDateField("custom_52")
  #2 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(111): CRM_Contact_BAO_SavedSearch::decodeRelativeFields((Array:11), "custom_52", "&gt;=", "35")
  #3 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(197): CRM_Contact_BAO_SavedSearch::getFormValues("custom_52")
  #4 sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(590): CRM_Contact_BAO_SavedSearch::getSearchParams("88")
  #5 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #6 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query-&gt;addGroupContactCache("132", NULL, "contact_a", "=")
  #7 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query-&gt;group((Array:5))
  #8 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query-&gt;whereClauseSingle((Array:5), NULL)
  #9 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query-&gt;whereClause(NULL)
  #10 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query-&gt;initialize(NULL)
  #11 sites/all/modules/civicrm/CRM/Contact/Selector.php(236): CRM_Contact_BAO_Query-&gt;__construct((Array:1), (Array:9), (Array:16), FALSE, FALSE, 1, FALSE, TRUE, FALSE, NULL, 1)
  #12 sites/all/modules/civicrm/CRM/Contact/Form/Search.php(832): CRM_Contact_Selector-&gt;__construct(NULL, (Array:5), (Array:1), (Array:9), 256, FALSE, TRUE, "smog", (Array:9))
  #13 sites/all/modules/civicrm/CRM/Contact/Form/Search/Basic.php(188): CRM_Contact_Form_Search-&gt;postProcess()
  #14 sites/all/modules/civicrm/CRM/Contact/Form/Search.php(718): CRM_Contact_Form_Search_Basic-&gt;postProcess()
  #15 sites/all/modules/civicrm/CRM/Contact/Form/Search/Basic.php(134): CRM_Contact_Form_Search-&gt;preProcess()
  #16 sites/all/modules/civicrm/CRM/Core/Form.php(531): CRM_Contact_Form_Search_Basic-&gt;preProcess()
  #17 sites/all/modules/civicrm/CRM/Core/QuickForm/Action/Display.php(92): CRM_Core_Form-&gt;buildForm()
  #18 sites/all/modules/civicrm/packages/HTML/QuickForm/Controller.php(203): CRM_Core_QuickForm_Action_Display-&gt;perform(Object(CRM_Contact_Form_Search_Basic), "display")
  #19 sites/all/modules/civicrm/packages/HTML/QuickForm/Page.php(103): HTML_QuickForm_Controller-&gt;handle(Object(CRM_Contact_Form_Search_Basic), "display")
  #20 sites/all/modules/civicrm/CRM/Core/Controller.php(351): HTML_QuickForm_Page-&gt;handle("display")
  #21 sites/all/modules/civicrm/CRM/Core/Invoke.php(310): CRM_Core_Controller-&gt;run((Array:3), (Array:0))
  #22 sites/all/modules/civicrm/CRM/Core/Invoke.php(84): CRM_Core_Invoke::runItem((Array:13))
  #23 sites/all/modules/civicrm/CRM/Core/Invoke.php(52): CRM_Core_Invoke::_invoke((Array:3))
  #24 sites/all/modules/civicrm/drupal/civicrm.module(448): CRM_Core_Invoke::invoke((Array:3))
  #25 /includes/menu.inc(527): civicrm_invoke("group", "search")
  #26 /index.php(21): menu_execute_active_handler()
  #27 {main}
  </code></pre>
  
  <h1>DEBUG INFO (sample 2)</h1>
  
  <p>CiviCRM_API3_Exception: "Expected one CustomField but found 0"</p>
  
  <pre><code>#0 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4491): civicrm_api3("CustomField", "getvalue", (Array:3))
  #1 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(452): CRM_Contact_BAO_Query::isCustomDateField("custom_21")
  #2 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(111): CRM_Contact_BAO_SavedSearch::decodeRelativeFields((Array:10), "custom_21", "BETWEEN", (Array:2))
  #3 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(197): CRM_Contact_BAO_SavedSearch::getFormValues("custom_21")
  #4 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(590): CRM_Contact_BAO_SavedSearch::getSearchParams("54")
  #5 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #6 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query-&gt;addGroupContactCache("89", NULL, "contact_a", "=")
  #7 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query-&gt;group((Array:5))
  #8 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query-&gt;whereClauseSingle((Array:5), NULL)
  #9 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query-&gt;whereClause(NULL)
  #10 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query-&gt;initialize(NULL)
  #11 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query-&gt;__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #12 /sites/all/modules/civicrm/CRM/Contact/BAO/Group.php(200): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #13 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(704): CRM_Contact_BAO_Group::getMember("89", FALSE)
  #14 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #15 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query-&gt;addGroupContactCache("77", NULL, "contact_a", "=")
  #16 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query-&gt;group((Array:5))
  #17 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query-&gt;whereClauseSingle((Array:5), NULL)
  #18 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query-&gt;whereClause(NULL)
  #19 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query-&gt;initialize(NULL)
  #20 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query-&gt;__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #21 /sites/all/modules/civicrm/CRM/Contact/BAO/Group.php(200): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #22 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(704): CRM_Contact_BAO_Group::getMember("77", FALSE)
  #23 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #24 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query-&gt;addGroupContactCache((Array:1), NULL, "contact_a", "IN")
  #25 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query-&gt;group((Array:5))
  #26 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query-&gt;whereClauseSingle((Array:5), NULL)
  #27 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query-&gt;whereClause(NULL)
  #28 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query-&gt;initialize(NULL)
  #29 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query-&gt;__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #30 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(229): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #31 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(208): CRM_Contact_BAO_GroupContactCache::add((Array:206))
  #32 /sites/all/modules/civicrm/CRM/Group/Page/Group.php(144): CRM_Contact_BAO_GroupContactCache::loadAll()
  #33 /sites/all/modules/civicrm/CRM/Core/Page/Basic.php(172): CRM_Group_Page_Group-&gt;browse(NULL, NULL)
  #34 /sites/all/modules/civicrm/CRM/Core/Invoke.php(310): CRM_Core_Page_Basic-&gt;run((Array:2), NULL)
  #35 /sites/all/modules/civicrm/CRM/Core/Invoke.php(84): CRM_Core_Invoke::runItem((Array:13))
  #36 /sites/all/modules/civicrm/CRM/Core/Invoke.php(52): CRM_Core_Invoke::_invoke((Array:2))
  #37 /sites/all/modules/civicrm/drupal/civicrm.module(448): CRM_Core_Invoke::invoke((Array:2))
  #38 /includes/menu.inc(527): civicrm_invoke("group")
  #39 /index.php(21): menu_execute_active_handler()
  #40 {main}
  </code></pre>
  
  <p>Could it be connected with some <strong>Summary Fields extension</strong> that has somehow messed up some custom fields? In any case, disabling <strong>Summary Fields</strong>, changing its settings or updating to newest version <strong>does not</strong> solve the issue.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-02-28T20:22:20.073Z
Comments.Text: Can you reach the Manage group listings? And then see the search criteria for any of the affected smart groups? (Settings> Edit Smart Group Criteria). Might give you a clue as to the fields the smart groups are based on.
Comments.UserDisplayName: Craig Almond
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-02-28T21:58:57.847Z
Comments.Text: there have been some issues with 'on hold' showing up in Smart Groups so check that when you 'edit' the saved search
Comments.UserDisplayName: petednz - fuzion
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-03-01T03:47:31.997Z
Comments.Text: We can better answer this question if you post the debugging and backtrace info.  Go to **Administer menu » System Settings » Debugging and Error Handling** and turn on debugging and backtrace.  Repeat the steps that lead to this error and you should get a much more detailed error message.  Please edit your question to include the expanded error + backtrace as text (i.e. not a screenshot).
Comments.UserDisplayName: Jon G - Megaphone Tech
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-03-01T08:31:54.923Z
Comments.Text: @CraigAlmond I'm afraid that **Edit Smart Group Criteria** renders the same error: *Expected one CustomField but found 0*
Comments.UserDisplayName: Aivars
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-03-01T08:39:05.507Z
Comments.Text: @JonG-MegaphoneTech Thank you! I added one instance of error with debug / backtrace enabled.
Comments.UserDisplayName: Aivars
Tags: <custom-fields><error>
Title: How to troubleshoot "Expected one CustomField but found 0" error?
ThreadText: # How to troubleshoot "Expected one CustomField but found 0" error?
  
  (Asked by: username_0 on 2019-02-28)
  
  When I try to open Contacts of some Smart Groups, CiviCRM gives me error:
  Expected one CustomField but found 0
  
  All parent Smart Groups that include faulty Smart Groups are also rendering the same error (can't open contacts).
  If I try to delete these Smart Groups, I get Network Error.
  
  When in Groups tab of Contact profile I open Smart Groups subsection, it remains empty (no Smart groups are listed). Not sure if for all contacts or only those that are included in faulty smart groups.
  How can I fix this error?
  CiviCRM 4.7.14 on Drupal 7.59
  DEBUG INFO (sample 1)
  CiviCRM_API3_Exception: "Expected one CustomField but found 0"
  #0 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4491): civicrm_api3("CustomField", "getvalue", (Array:3))
  #1 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(452): CRM_Contact_BAO_Query::isCustomDateField("custom_52")
  #2 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(111): CRM_Contact_BAO_SavedSearch::decodeRelativeFields((Array:11), "custom_52", ">=", "35")
  #3 sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(197): CRM_Contact_BAO_SavedSearch::getFormValues("custom_52")
  #4 sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(590): CRM_Contact_BAO_SavedSearch::getSearchParams("88")
  #5 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #6 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query->addGroupContactCache("132", NULL, "contact_a", "=")
  #7 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query->group((Array:5))
  #8 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query->whereClauseSingle((Array:5), NULL)
  #9 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query->whereClause(NULL)
  #10 sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query->initialize(NULL)
  #11 sites/all/modules/civicrm/CRM/Contact/Selector.php(236): CRM_Contact_BAO_Query->__construct((Array:1), (Array:9), (Array:16), FALSE, FALSE, 1, FALSE, TRUE, FALSE, NULL, 1)
  #12 sites/all/modules/civicrm/CRM/Contact/Form/Search.php(832): CRM_Contact_Selector->__construct(NULL, (Array:5), (Array:1), (Array:9), 256, FALSE, TRUE, "smog", (Array:9))
  #13 sites/all/modules/civicrm/CRM/Contact/Form/Search/Basic.php(188): CRM_Contact_Form_Search->postProcess()
  #14 sites/all/modules/civicrm/CRM/Contact/Form/Search.php(718): CRM_Contact_Form_Search_Basic->postProcess()
  #15 sites/all/modules/civicrm/CRM/Contact/Form/Search/Basic.php(134): CRM_Contact_Form_Search->preProcess()
  #16 sites/all/modules/civicrm/CRM/Core/Form.php(531): CRM_Contact_Form_Search_Basic->preProcess()
  #17 sites/all/modules/civicrm/CRM/Core/QuickForm/Action/Display.php(92): CRM_Core_Form->buildForm()
  #18 sites/all/modules/civicrm/packages/HTML/QuickForm/Controller.php(203): CRM_Core_QuickForm_Action_Display->perform(Object(CRM_Contact_Form_Search_Basic), "display")
  #19 sites/all/modules/civicrm/packages/HTML/QuickForm/Page.php(103): HTML_QuickForm_Controller->handle(Object(CRM_Contact_Form_Search_Basic), "display")
  #20 sites/all/modules/civicrm/CRM/Core/Controller.php(351): HTML_QuickForm_Page->handle("display")
  #21 sites/all/modules/civicrm/CRM/Core/Invoke.php(310): CRM_Core_Controller->run((Array:3), (Array:0))
  #22 sites/all/modules/civicrm/CRM/Core/Invoke.php(84): CRM_Core_Invoke::runItem((Array:13))
  #23 sites/all/modules/civicrm/CRM/Core/Invoke.php(52): CRM_Core_Invoke::_invoke((Array:3))
  #24 sites/all/modules/civicrm/drupal/civicrm.module(448): CRM_Core_Invoke::invoke((Array:3))
  #25 /includes/menu.inc(527): civicrm_invoke("group", "search")
  #26 /index.php(21): menu_execute_active_handler()
  #27 {main}
  
  DEBUG INFO (sample 2)
  CiviCRM_API3_Exception: "Expected one CustomField but found 0"
  #0 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4491): civicrm_api3("CustomField", "getvalue", (Array:3))
  #1 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(452): CRM_Contact_BAO_Query::isCustomDateField("custom_21")
  #2 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(111): CRM_Contact_BAO_SavedSearch::decodeRelativeFields((Array:10), "custom_21", "BETWEEN", (Array:2))
  #3 /sites/all/modules/civicrm/CRM/Contact/BAO/SavedSearch.php(197): CRM_Contact_BAO_SavedSearch::getFormValues("custom_21")
  #4 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(590): CRM_Contact_BAO_SavedSearch::getSearchParams("54")
  #5 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #6 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query->addGroupContactCache("89", NULL, "contact_a", "=")
  #7 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query->group((Array:5))
  #8 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query->whereClauseSingle((Array:5), NULL)
  #9 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query->whereClause(NULL)
  #10 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query->initialize(NULL)
  #11 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query->__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #12 /sites/all/modules/civicrm/CRM/Contact/BAO/Group.php(200): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #13 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(704): CRM_Contact_BAO_Group::getMember("89", FALSE)
  #14 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #15 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query->addGroupContactCache("77", NULL, "contact_a", "=")
  #16 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query->group((Array:5))
  #17 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query->whereClauseSingle((Array:5), NULL)
  #18 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query->whereClause(NULL)
  #19 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query->initialize(NULL)
  #20 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query->__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #21 /sites/all/modules/civicrm/CRM/Contact/BAO/Group.php(200): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #22 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(704): CRM_Contact_BAO_Group::getMember("77", FALSE)
  #23 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(3054): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
  #24 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2947): CRM_Contact_BAO_Query->addGroupContactCache((Array:1), NULL, "contact_a", "IN")
  #25 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(1794): CRM_Contact_BAO_Query->group((Array:5))
  #26 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(2021): CRM_Contact_BAO_Query->whereClauseSingle((Array:5), NULL)
  #27 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(502): CRM_Contact_BAO_Query->whereClause(NULL)
  #28 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(466): CRM_Contact_BAO_Query->initialize(NULL)
  #29 /sites/all/modules/civicrm/CRM/Contact/BAO/Query.php(4330): CRM_Contact_BAO_Query->__construct((Array:1), (Array:1), (Array:16), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL)
  #30 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(229): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
  #31 /sites/all/modules/civicrm/CRM/Contact/BAO/GroupContactCache.php(208): CRM_Contact_BAO_GroupContactCache::add((Array:206))
  #32 /sites/all/modules/civicrm/CRM/Group/Page/Group.php(144): CRM_Contact_BAO_GroupContactCache::loadAll()
  #33 /sites/all/modules/civicrm/CRM/Core/Page/Basic.php(172): CRM_Group_Page_Group->browse(NULL, NULL)
  #34 /sites/all/modules/civicrm/CRM/Core/Invoke.php(310): CRM_Core_Page_Basic->run((Array:2), NULL)
  #35 /sites/all/modules/civicrm/CRM/Core/Invoke.php(84): CRM_Core_Invoke::runItem((Array:13))
  #36 /sites/all/modules/civicrm/CRM/Core/Invoke.php(52): CRM_Core_Invoke::_invoke((Array:2))
  #37 /sites/all/modules/civicrm/drupal/civicrm.module(448): CRM_Core_Invoke::invoke((Array:2))
  #38 /includes/menu.inc(527): civicrm_invoke("group")
  #39 /index.php(21): menu_execute_active_handler()
  #40 {main}
  
  Could it be connected with some Summary Fields extension that has somehow messed up some custom fields? In any case, disabling Summary Fields, changing its settings or updating to newest version does not solve the issue.
  
  **Tags:** custom-fields, error
  
  > **Comments:**
  > **username_1**: Can you reach the Manage group listings? And then see the search criteria for any of the affected smart groups? (Settings> Edit Smart Group Criteria). Might give you a clue as to the fields the smart groups are based on.  
  > **username_2**: there have been some issues with 'on hold' showing up in Smart Groups so check that when you 'edit' the saved search  
  > **username_3**: We can better answer this question if you post the debugging and backtrace info.  Go to **Administer menu » System Settings » Debugging and Error Handling** and turn on debugging and backtrace.  Repeat the steps that lead to this error and you should get a much more detailed error message.  Please edit your question to include the expanded error + backtrace as text (i.e. not a screenshot).  
  > **username_0**: @CraigAlmond I'm afraid that **Edit Smart Group Criteria** renders the same error: *Expected one CustomField but found 0*  
  > **username_0**: @JonG-MegaphoneTech Thank you! I added one instance of error with debug / backtrace enabled.  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_3 on 2019-03-02. Score: 1
  
  These smart groups include custom fields that no longer exist. In the first case, it's the custom field with id of 52; in the second the id is 21. These smart groups should have their criteria modified to reflect the fact that these groups no longer exist.
  
  > **Comments:**
  > **username_0**: How can I do it, if the standard way - **Edit Smart Group Criteria** - produces the same error?  
  
  ---
  
  ### Answer by username_0 on 2019-03-29. Score: 1
  
  @junglebird on <https://chat.civicrm.org/civicrm> provided a solution to delete such groups via API Explorer.
  
  Smart groups also have an entry in **civicrm\_saved\_search**. I think it would be safer to make a list of the group IDs, go to **Support >> Developer >> API Explorer** and select Entity of **Group**, Action of **Delete**, and set the ID accordingly.
  
  > **Comments:**
  > **username_3**: This is me - I should try harder to consolidate my CiviCRM usernames :)  
  
  ---
  
  