A Tricky Forms Problem

I recently wrote a WordPress plug-in that incorporated a form.  The page displayed just fine, but whenever I posted the form’s results Apache returned a 404 Page Not Found error.  How could that be?  I was just on that page!

The Internet To The Rescue

A search of the issue resulted in me finding this page, which exactly described my problem and why it was happening.  It turns out that there are a whole raft of reserved names from form input elements, and one of them, “hour”, I was using.  This was the cause of the problem.  As soon as I changed it to something not likely to be reserved, the form post worked just fine.

The Lesson Learned

Because it is impossible to know all the reserved words, and they probably change all the time, the best way is to prefix all your input name tags with something that will not likely appear in the list.  For example:

<input type=”text” name=”tgg_hour”>

It really doesn’t matter what the prefix is, just make it something unusual.

List of reserved names in $_POST and $_REQUEST used by WordPress 3.5

In case the above link is broken I have reproduced the list below.  As the original author said, it’s probably incomplete.

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-->admin_email<!-- [et_pb_line_break_holder] -->admin_password<!-- [et_pb_line_break_holder] -->admin_password2<!-- [et_pb_line_break_holder] -->ajax<!-- [et_pb_line_break_holder] -->align<!-- [et_pb_line_break_holder] -->allblogs<!-- [et_pb_line_break_holder] -->allusers<!-- [et_pb_line_break_holder] -->alt<!-- [et_pb_line_break_holder] -->approve_parent<!-- [et_pb_line_break_holder] -->approved<!-- [et_pb_line_break_holder] -->attachment<!-- [et_pb_line_break_holder] -->attachment_id<!-- [et_pb_line_break_holder] -->attachments<!-- [et_pb_line_break_holder] -->auth_cookie<!-- [et_pb_line_break_holder] -->author<!-- [et_pb_line_break_holder] -->author_name<!-- [et_pb_line_break_holder] -->autocomplete_type<!-- [et_pb_line_break_holder] -->auto_draft<!-- [et_pb_line_break_holder] -->auto-add-pages<!-- [et_pb_line_break_holder] -->autosave<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->background-attachment<!-- [et_pb_line_break_holder] -->background-color<!-- [et_pb_line_break_holder] -->background-position-x<!-- [et_pb_line_break_holder] -->background-repeat<!-- [et_pb_line_break_holder] -->banned_email_domains<!-- [et_pb_line_break_holder] -->blog<!-- [et_pb_line_break_holder] -->blog_name<!-- [et_pb_line_break_holder] -->blog_public<!-- [et_pb_line_break_holder] -->blog_upload_space<!-- [et_pb_line_break_holder] -->blogname<!-- [et_pb_line_break_holder] -->bulk_edit<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->c<!-- [et_pb_line_break_holder] -->calendar<!-- [et_pb_line_break_holder] -->cat<!-- [et_pb_line_break_holder] -->category_base<!-- [et_pb_line_break_holder] -->category_name<!-- [et_pb_line_break_holder] -->catslist<!-- [et_pb_line_break_holder] -->changeit<!-- [et_pb_line_break_holder] -->changes<!-- [et_pb_line_break_holder] -->charset<!-- [et_pb_line_break_holder] -->checkbox<!-- [et_pb_line_break_holder] -->checked<!-- [et_pb_line_break_holder] -->clear-recent-list<!-- [et_pb_line_break_holder] -->closed<!-- [et_pb_line_break_holder] -->comment<!-- [et_pb_line_break_holder] -->comment_approved<!-- [et_pb_line_break_holder] -->comment_author<!-- [et_pb_line_break_holder] -->comment_author_email<!-- [et_pb_line_break_holder] -->comment_author_url<!-- [et_pb_line_break_holder] -->comment_content<!-- [et_pb_line_break_holder] -->comment_date<!-- [et_pb_line_break_holder] -->comment_ID<!-- [et_pb_line_break_holder] -->comment_parent<!-- [et_pb_line_break_holder] -->comment_post_ID<!-- [et_pb_line_break_holder] -->comment_shortcuts<!-- [et_pb_line_break_holder] -->comment_status<!-- [et_pb_line_break_holder] -->comments_listing<!-- [et_pb_line_break_holder] -->comments_popup<!-- [et_pb_line_break_holder] -->confirmdelete<!-- [et_pb_line_break_holder] -->connection_type<!-- [et_pb_line_break_holder] -->content<!-- [et_pb_line_break_holder] -->context<!-- [et_pb_line_break_holder] -->cpage<!-- [et_pb_line_break_holder] -->create-new-attachment<!-- [et_pb_line_break_holder] -->createuser<!-- [et_pb_line_break_holder] -->customize_messenger_channel<!-- [et_pb_line_break_holder] -->customized<!-- [et_pb_line_break_holder] -->customlink-tab<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->date<!-- [et_pb_line_break_holder] -->date_format<!-- [et_pb_line_break_holder] -->date_format_custom<!-- [et_pb_line_break_holder] -->day<!-- [et_pb_line_break_holder] -->default-header<!-- [et_pb_line_break_holder] -->delete<!-- [et_pb_line_break_holder] -->delete_all<!-- [et_pb_line_break_holder] -->delete_all2<!-- [et_pb_line_break_holder] -->delete_comments<!-- [et_pb_line_break_holder] -->delete_option<!-- [et_pb_line_break_holder] -->delete_tags<!-- [et_pb_line_break_holder] -->delete_widget<!-- [et_pb_line_break_holder] -->deletebookmarks<!-- [et_pb_line_break_holder] -->deletecomment<!-- [et_pb_line_break_holder] -->deleted<!-- [et_pb_line_break_holder] -->deletemeta<!-- [et_pb_line_break_holder] -->deletepost<!-- [et_pb_line_break_holder] -->description<!-- [et_pb_line_break_holder] -->detached<!-- [et_pb_line_break_holder] -->dismiss<!-- [et_pb_line_break_holder] -->display_name<!-- [et_pb_line_break_holder] -->do<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->edit_date<!-- [et_pb_line_break_holder] -->email<!-- [et_pb_line_break_holder] -->error<!-- [et_pb_line_break_holder] -->exact<!-- [et_pb_line_break_holder] -->excerpt<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->features<!-- [et_pb_line_break_holder] -->feed<!-- [et_pb_line_break_holder] -->fetch<!-- [et_pb_line_break_holder] -->fheight<!-- [et_pb_line_break_holder] -->file<!-- [et_pb_line_break_holder] -->fileupload_maxk<!-- [et_pb_line_break_holder] -->filter<!-- [et_pb_line_break_holder] -->find_detached<!-- [et_pb_line_break_holder] -->first_comment<!-- [et_pb_line_break_holder] -->first_comment_author<!-- [et_pb_line_break_holder] -->first_comment_url<!-- [et_pb_line_break_holder] -->first_name<!-- [et_pb_line_break_holder] -->first_page<!-- [et_pb_line_break_holder] -->first_post<!-- [et_pb_line_break_holder] -->found_post_id<!-- [et_pb_line_break_holder] -->fwidth<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->global_terms_enabled<!-- [et_pb_line_break_holder] -->GLOBALS<!-- [et_pb_line_break_holder] -->gmt_offset<!-- [et_pb_line_break_holder] -->guid<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->height<!-- [et_pb_line_break_holder] -->hh<!-- [et_pb_line_break_holder] -->hidden<!-- [et_pb_line_break_holder] -->hidden_aa<!-- [et_pb_line_break_holder] -->hidden_jj<!-- [et_pb_line_break_holder] -->hidden_mm<!-- [et_pb_line_break_holder] -->hidden_mn<!-- [et_pb_line_break_holder] -->hidden_hh<!-- [et_pb_line_break_holder] -->history<!-- [et_pb_line_break_holder] -->hostname<!-- [et_pb_line_break_holder] -->hour<!-- [et_pb_line_break_holder] -->html-upload<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->id<!-- [et_pb_line_break_holder] -->ID<!-- [et_pb_line_break_holder] -->ids<!-- [et_pb_line_break_holder] -->id_base<!-- [et_pb_line_break_holder] -->illegal_names<!-- [et_pb_line_break_holder] -->insert-gallery<!-- [et_pb_line_break_holder] -->insertonlybutton<!-- [et_pb_line_break_holder] -->interim-login<!-- [et_pb_line_break_holder] -->item-object<!-- [et_pb_line_break_holder] -->item-type<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->jj<!-- [et_pb_line_break_holder] -->json<!-- [et_pb_line_break_holder] -->json_data<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->key<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->last_name<!-- [et_pb_line_break_holder] -->limited_email_domains<!-- [et_pb_line_break_holder] -->link_id<!-- [et_pb_line_break_holder] -->link_image<!-- [et_pb_line_break_holder] -->link_name<!-- [et_pb_line_break_holder] -->link_rss<!-- [et_pb_line_break_holder] -->link_url<!-- [et_pb_line_break_holder] -->link_visible<!-- [et_pb_line_break_holder] -->linkcheck<!-- [et_pb_line_break_holder] -->locale<!-- [et_pb_line_break_holder] -->locked<!-- [et_pb_line_break_holder] -->log<!-- [et_pb_line_break_holder] -->logged_in_cookie<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->m<!-- [et_pb_line_break_holder] -->media<!-- [et_pb_line_break_holder] -->media_type<!-- [et_pb_line_break_holder] -->menu<!-- [et_pb_line_break_holder] -->menu_items<!-- [et_pb_line_break_holder] -->menu-item<!-- [et_pb_line_break_holder] -->menu-item-attr-title<!-- [et_pb_line_break_holder] -->menu-item-classes<!-- [et_pb_line_break_holder] -->menu-item-db-id<!-- [et_pb_line_break_holder] -->menu-item-description<!-- [et_pb_line_break_holder] -->menu-item-object<!-- [et_pb_line_break_holder] -->menu-item-object-id<!-- [et_pb_line_break_holder] -->menu-item-parent-id<!-- [et_pb_line_break_holder] -->menu-item-position<!-- [et_pb_line_break_holder] -->menu-item-target<!-- [et_pb_line_break_holder] -->menu-item-title<!-- [et_pb_line_break_holder] -->menu-item-type<!-- [et_pb_line_break_holder] -->menu-item-url<!-- [et_pb_line_break_holder] -->menu-item-xfn<!-- [et_pb_line_break_holder] -->menu-locations<!-- [et_pb_line_break_holder] -->menu-name<!-- [et_pb_line_break_holder] -->message<!-- [et_pb_line_break_holder] -->meta<!-- [et_pb_line_break_holder] -->metakeyinput<!-- [et_pb_line_break_holder] -->metakeyselect<!-- [et_pb_line_break_holder] -->metavalue<!-- [et_pb_line_break_holder] -->minute<!-- [et_pb_line_break_holder] -->mm<!-- [et_pb_line_break_holder] -->mn<!-- [et_pb_line_break_holder] -->mode<!-- [et_pb_line_break_holder] -->monthnum<!-- [et_pb_line_break_holder] -->more<!-- [et_pb_line_break_holder] -->move<!-- [et_pb_line_break_holder] -->multi_number<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->name<!-- [et_pb_line_break_holder] -->nav-menu-locations<!-- [et_pb_line_break_holder] -->new<!-- [et_pb_line_break_holder] -->new_role<!-- [et_pb_line_break_holder] -->new_slug<!-- [et_pb_line_break_holder] -->new_title<!-- [et_pb_line_break_holder] -->newcat<!-- [et_pb_line_break_holder] -->newcomment_author<!-- [et_pb_line_break_holder] -->newcomment_author_email<!-- [et_pb_line_break_holder] -->newcomment_author_url<!-- [et_pb_line_break_holder] -->newcontent<!-- [et_pb_line_break_holder] -->newuser<!-- [et_pb_line_break_holder] -->nickname<!-- [et_pb_line_break_holder] -->no_placeholder<!-- [et_pb_line_break_holder] -->noapi<!-- [et_pb_line_break_holder] -->noconfirmation<!-- [et_pb_line_break_holder] -->noredir<!-- [et_pb_line_break_holder] -->number<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->offset<!-- [et_pb_line_break_holder] -->oitar<!-- [et_pb_line_break_holder] -->option<!-- [et_pb_line_break_holder] -->option_page<!-- [et_pb_line_break_holder] -->order<!-- [et_pb_line_break_holder] -->orderby<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->p<!-- [et_pb_line_break_holder] -->pb<!-- [et_pb_line_break_holder] -->page<!-- [et_pb_line_break_holder] -->page_columns<!-- [et_pb_line_break_holder] -->page_id<!-- [et_pb_line_break_holder] -->page_options<!-- [et_pb_line_break_holder] -->paged<!-- [et_pb_line_break_holder] -->pagegen_timestamp<!-- [et_pb_line_break_holder] -->pagename<!-- [et_pb_line_break_holder] -->parent_id<!-- [et_pb_line_break_holder] -->pass1<!-- [et_pb_line_break_holder] -->pass2<!-- [et_pb_line_break_holder] -->password<!-- [et_pb_line_break_holder] -->permalink_structure<!-- [et_pb_line_break_holder] -->photo_description<!-- [et_pb_line_break_holder] -->photo_src<!-- [et_pb_line_break_holder] -->phperror<!-- [et_pb_line_break_holder] -->ping_status<!-- [et_pb_line_break_holder] -->plugin<!-- [et_pb_line_break_holder] -->plugin_status<!-- [et_pb_line_break_holder] -->pointer<!-- [et_pb_line_break_holder] -->position<!-- [et_pb_line_break_holder] -->post<!-- [et_pb_line_break_holder] -->post_category<!-- [et_pb_line_break_holder] -->post_data<!-- [et_pb_line_break_holder] -->post_format<!-- [et_pb_line_break_holder] -->post_ID<!-- [et_pb_line_break_holder] -->post_id<!-- [et_pb_line_break_holder] -->post_mime_type<!-- [et_pb_line_break_holder] -->post_password<!-- [et_pb_line_break_holder] -->post_status<!-- [et_pb_line_break_holder] -->post_title<!-- [et_pb_line_break_holder] -->post_type<!-- [et_pb_line_break_holder] -->post_view<!-- [et_pb_line_break_holder] -->postid<!-- [et_pb_line_break_holder] -->posts<!-- [et_pb_line_break_holder] -->preview<!-- [et_pb_line_break_holder] -->primary_blog<!-- [et_pb_line_break_holder] -->private_key<!-- [et_pb_line_break_holder] -->ps<!-- [et_pb_line_break_holder] -->public_key<!-- [et_pb_line_break_holder] -->publish<!-- [et_pb_line_break_holder] -->pwd<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->query<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->reassign_user<!-- [et_pb_line_break_holder] -->reauth<!-- [et_pb_line_break_holder] -->redirect<!-- [et_pb_line_break_holder] -->redirect_to<!-- [et_pb_line_break_holder] -->ref<!-- [et_pb_line_break_holder] -->referredby<!-- [et_pb_line_break_holder] -->registration<!-- [et_pb_line_break_holder] -->registrationnotification<!-- [et_pb_line_break_holder] -->rememberme<!-- [et_pb_line_break_holder] -->remove-background<!-- [et_pb_line_break_holder] -->removeheader<!-- [et_pb_line_break_holder] -->removewidget<!-- [et_pb_line_break_holder] -->reset-background<!-- [et_pb_line_break_holder] -->resetheader<!-- [et_pb_line_break_holder] -->review<!-- [et_pb_line_break_holder] -->rich_editing<!-- [et_pb_line_break_holder] -->robots<!-- [et_pb_line_break_holder] -->role<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->s<!-- [et_pb_line_break_holder] -->same<!-- [et_pb_line_break_holder] -->save<!-- [et_pb_line_break_holder] -->savewidget<!-- [et_pb_line_break_holder] -->savewidgets<!-- [et_pb_line_break_holder] -->screen<!-- [et_pb_line_break_holder] -->scrollto<!-- [et_pb_line_break_holder] -->search<!-- [et_pb_line_break_holder] -->second<!-- [et_pb_line_break_holder] -->section<!-- [et_pb_line_break_holder] -->selectall<!-- [et_pb_line_break_holder] -->selection<!-- [et_pb_line_break_holder] -->send<!-- [et_pb_line_break_holder] -->send_password<!-- [et_pb_line_break_holder] -->sentence<!-- [et_pb_line_break_holder] -->short<!-- [et_pb_line_break_holder] -->show_sticky<!-- [et_pb_line_break_holder] -->sidebar<!-- [et_pb_line_break_holder] -->sidebars<!-- [et_pb_line_break_holder] -->signup_for<!-- [et_pb_line_break_holder] -->signup_form_id<!-- [et_pb_line_break_holder] -->site_id<!-- [et_pb_line_break_holder] -->site_name<!-- [et_pb_line_break_holder] -->sitename<!-- [et_pb_line_break_holder] -->size<!-- [et_pb_line_break_holder] -->skip-cropping<!-- [et_pb_line_break_holder] -->spam<!-- [et_pb_line_break_holder] -->spammed<!-- [et_pb_line_break_holder] -->src<!-- [et_pb_line_break_holder] -->ss<!-- [et_pb_line_break_holder] -->stage<!-- [et_pb_line_break_holder] -->start<!-- [et_pb_line_break_holder] -->static<!-- [et_pb_line_break_holder] -->status<!-- [et_pb_line_break_holder] -->sticky<!-- [et_pb_line_break_holder] -->subdomain_install<!-- [et_pb_line_break_holder] -->submit<!-- [et_pb_line_break_holder] -->subpost<!-- [et_pb_line_break_holder] -->subpost_id<!-- [et_pb_line_break_holder] -->super_admin<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->tab<!-- [et_pb_line_break_holder] -->tag<!-- [et_pb_line_break_holder] -->tag_ID<!-- [et_pb_line_break_holder] -->tag-name<!-- [et_pb_line_break_holder] -->tag_base<!-- [et_pb_line_break_holder] -->tags_input<!-- [et_pb_line_break_holder] -->tax<!-- [et_pb_line_break_holder] -->tax_input<!-- [et_pb_line_break_holder] -->tag-name<!-- [et_pb_line_break_holder] -->target<!-- [et_pb_line_break_holder] -->taxonomy<!-- [et_pb_line_break_holder] -->tb<!-- [et_pb_line_break_holder] -->term<!-- [et_pb_line_break_holder] -->text-color<!-- [et_pb_line_break_holder] -->the-widget-id<!-- [et_pb_line_break_holder] -->theme<!-- [et_pb_line_break_holder] -->theme_status<!-- [et_pb_line_break_holder] -->thumb<!-- [et_pb_line_break_holder] -->timezone_string<!-- [et_pb_line_break_holder] -->time_format<!-- [et_pb_line_break_holder] -->time_format_custom<!-- [et_pb_line_break_holder] -->title<!-- [et_pb_line_break_holder] -->thumbnail_id<!-- [et_pb_line_break_holder] -->trash<!-- [et_pb_line_break_holder] -->trashed<!-- [et_pb_line_break_holder] -->type<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->undismiss<!-- [et_pb_line_break_holder] -->unspam<!-- [et_pb_line_break_holder] -->unspammed<!-- [et_pb_line_break_holder] -->untrash<!-- [et_pb_line_break_holder] -->untrashed<!-- [et_pb_line_break_holder] -->url<!-- [et_pb_line_break_holder] -->update_home_url<!-- [et_pb_line_break_holder] -->updated<!-- [et_pb_line_break_holder] -->upgrade<!-- [et_pb_line_break_holder] -->upload_filetypes<!-- [et_pb_line_break_holder] -->upload_space_check_disabled<!-- [et_pb_line_break_holder] -->use_ssl<!-- [et_pb_line_break_holder] -->user<!-- [et_pb_line_break_holder] -->user_id<!-- [et_pb_line_break_holder] -->user_login<!-- [et_pb_line_break_holder] -->user_name<!-- [et_pb_line_break_holder] -->username<!-- [et_pb_line_break_holder] -->users<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->verify-delete<!-- [et_pb_line_break_holder] -->version<!-- [et_pb_line_break_holder] -->visibility<!-- [et_pb_line_break_holder] -->visible<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->w<!-- [et_pb_line_break_holder] -->weblog_title<!-- [et_pb_line_break_holder] -->welcome_email<!-- [et_pb_line_break_holder] -->welcome_user_email<!-- [et_pb_line_break_holder] -->widget_id<!-- [et_pb_line_break_holder] -->widget_number<!-- [et_pb_line_break_holder] -->widget-id<!-- [et_pb_line_break_holder] -->widget-recent-comments<!-- [et_pb_line_break_holder] -->widget-rss<!-- [et_pb_line_break_holder] -->width<!-- [et_pb_line_break_holder] -->withcomments<!-- [et_pb_line_break_holder] -->withoutcomments<!-- [et_pb_line_break_holder] -->wp_customize<!-- [et_pb_line_break_holder] -->wp_http_referer<!-- [et_pb_line_break_holder] -->wp_screen_options<!-- [et_pb_line_break_holder] -->wp-preview<!-- [et_pb_line_break_holder] -->WPLANG<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->x1<!-- [et_pb_line_break_holder] --><!-- [et_pb_line_break_holder] -->y1<!-- [et_pb_line_break_holder] -->year<!-- [et_pb_line_break_holder] --></pre><!-- [et_pb_line_break_holder] -->