AJAX HTTP error renders Views UI useless.

Hi

I tried to set up my first view on D7, tried to add a Field, but then got below error, anyone any ideas?

Not sure if related, but I also get an Ajax error when trying to upgrade modules.

An AJAX HTTP error occurred.
HTTP Result Code: 200
Debugging information follows.
Path: /site/admin/structure/views/ajax/add-item/homepage_right_box_1_view/default/field
StatusText: OK
ResponseText: [{"command":"settings","settings":{"basePath":"\/site\/","ajaxPageState":{"theme":"seven","theme_token":"PxoKAhCH0gSlKCboAnxaR9ZyAa3cCtYDBKxVnooY9Vc","css":[]}},"merge":true},{"command":"viewsSetForm","output":"\u003cform action=\"\/site\/admin\/structure\/views\/ajax\/add-item\/homepage_right_box_1_view\/default\/field\" method=\"post\" id=\"views-ui-add-item-form\" accept-charset=\"UTF-8\"\u003e\u003cdiv\u003e\u003cdiv class=\"form-item form-type-select form-item-group\"\u003e\n \u003clabel for=\"edit-group\"\u003eGroups \u003c\/label\u003e\n \u003cselect class=\"ctools-master-dependent form-select\" id=\"edit-group\" name=\"group\"\u003e\u003coption value=\"all\"\u003e- All -\u003c\/option\u003e\u003coption value=\"comment\"\u003eComment\u003c\/option\u003e\u003coption value=\"fields\"\u003eFields\u003c\/option\u003e\u003coption value=\"file-usage\"\u003eFile Usage\u003c\/option\u003e\u003coption value=\"global\"\u003eGlobal\u003c\/option\u003e\u003coption value=\"node\"\u003eNode\u003c\/option\u003e\u003coption value=\"node-revision\"\u003eNode revision\u003c\/option\u003e\u003coption value=\"search\"\u003eSearch\u003c\/option\u003e\u003coption value=\"taxonomy\"\u003eTaxonomy\u003c\/option\u003e\u003coption value=\"user\"\u003eUser\u003c\/option\u003e\u003c\/select\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"views-radio-box form-checkboxes\"\u003e\u003cdiv class=\"ctools-dependent-all ctools-dependent-comment\"\u003e\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.status\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentstatus\" name=\"name[comment.status]\" value=\"comment.status\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentstatus\"\u003eComment: Approved \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eWhether the comment is approved (or still in the moderation queue).\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.name\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentname\" name=\"name[comment.name]\" value=\"comment.name\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentname\"\u003eComment: Author \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eThe name of the comment's author. Can be rendered as a link to the author's homepage.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.homepage\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commenthomepage\" name=\"name[comment.homepage]\" value=\"comment.homepage\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commenthomepage\"\u003eComment: Author's website \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eThe website address of the comment's author. Can be rendered as a link. Will be empty if the author is a registered user.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.delete-comment\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentdelete-comment\" name=\"name[comment.delete_comment]\" value=\"comment.delete_comment\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentdelete-comment\"\u003eComment: Delete link \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eProvide a simple link to delete the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.thread\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentthread\" name=\"name[comment.thread]\" value=\"comment.thread\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentthread\"\u003eComment: Depth \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eDisplay the depth of the comment if it is threaded.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.edit-comment\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentedit-comment\" name=\"name[comment.edit_comment]\" value=\"comment.edit_comment\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentedit-comment\"\u003eComment: Edit link \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eProvide a simple link to edit the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.hostname\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commenthostname\" name=\"name[comment.hostname]\" value=\"comment.hostname\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commenthostname\"\u003eComment: Hostname \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eHostname of user that posted the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.cid\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentcid\" name=\"name[comment.cid]\" value=\"comment.cid\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentcid\"\u003eComment: ID \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eThe comment ID of the field\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.mail\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentmail\" name=\"name[comment.mail]\" value=\"comment.mail\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentmail\"\u003eComment: Mail \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eEmail of user that posted the comment. Will be empty if the author is a registered user.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.pid\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentpid\" name=\"name[comment.pid]\" value=\"comment.pid\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentpid\"\u003eComment: Parent CID \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eThe Comment ID of the parent comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.created\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentcreated\" name=\"name[comment.created]\" value=\"comment.created\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentcreated\"\u003eComment: Post date \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eDate and time of when the comment was created.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.changed\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentchanged\" name=\"name[comment.changed]\" value=\"comment.changed\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentchanged\"\u003eComment: Post date \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eDate and time of when the comment was last updated.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.replyto-comment\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentreplyto-comment\" name=\"name[comment.replyto_comment]\" value=\"comment.replyto_comment\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentreplyto-comment\"\u003eComment: Reply-to link \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eProvide a simple link to reply to the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.subject\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentsubject\" name=\"name[comment.subject]\" value=\"comment.subject\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentsubject\"\u003eComment: Title \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eThe title of the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-comment.view-comment\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-commentview-comment\" name=\"name[comment.view_comment]\" value=\"comment.view_comment\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-commentview-comment\"\u003eComment: View link \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eProvide a simple link to view the comment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv class=\"ctools-dependent-all ctools-dependent-fields\"\u003e\u003cdiv class=\"form-item form-type-checkbox form-item-name-field-data-body.entity-id\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-field-data-bodyentity-id\" name=\"name[field_data_body.entity_id]\" value=\"field_data_body.entity_id\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-field-data-bodyentity-id\"\u003eFields: body \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eAppears in: node:page, node:article, node:homepage_right_box_1\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"form-item form-type-checkbox form-item-name-field-data-field-image.entity-id\"\u003e\n \u003cinput type=\"checkbox\" id=\"edit-name-field-data-field-imageentity-id\" name=\"name[field_data_field_image.entity_id]\" value=\"field_data_field_image.entity_id\" class=\"form-checkbox\" \/\u003e \u003clabel class=\"option\" for=\"edit-name-field-data-field-imageentity-id\"\u003eFields: field_image \u003c\/label\u003e\n\n\u003cdiv class=\"description\"\u003eAppears in: node:article\u003c\