Title: error 404 Last modified: September 30, 2021 --- # error 404 * [albertpasto](https://wordpress.org/support/users/albertpasto/) * (@albertpasto) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/) * It returns me 404 error to old links. If I create new links, no problem * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ferror-404-71%2F%3Foutput_format%3Dmd&locale=en_US) to see the link]_ Viewing 8 replies - 1 through 8 (of 8 total) * Plugin Contributor [nwjames](https://wordpress.org/support/users/nwjames/) * (@nwjames) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14933547) * [@albertpasto](https://wordpress.org/support/users/albertpasto/), When you enter a URL like `http://coralmaristes.cat/documents/2021/04/adiosnonino.pdf`since it is not a file at this address, it will do via the rewrite rules. * The delivered rule for this, if active, will transform this input into `http:// coralmaristes.cat/index.php?year=2021&monthnum=04&document=adiosnonino` * When I enter that URL, I could not find that document. * I entered `http://coralmaristes.cat/documents/` which should return a list of all published oocuments and it returned a list of 7 documents – 2 of which returned a 404. * “adiosnonino” was not amongst them. * This needs to be the post_name of the document post. * Possibly an initial check is to ensure that the Permalinks are refreshed by going to Settings -> Permalinks and clicking on the Save Changes button. You should not change anything. * Hope that this gives you some pointers to resolving the issue. Neil James * Thread Starter [albertpasto](https://wordpress.org/support/users/albertpasto/) * (@albertpasto) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14933803) * No. I have already updated the permanent links. Out of order. I think the broken links originated from a web server change. Most of them work, but for some reason, a few dozen have broken. In fact, the appearance of the pluggin itself next to the administrator is different. * [https://photos.app.goo.gl/McYs5afijJLe6DSi7](https://photos.app.goo.gl/McYs5afijJLe6DSi7) * Plugin Contributor [nwjames](https://wordpress.org/support/users/nwjames/) * (@nwjames) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14937080) * [@albertpasto](https://wordpress.org/support/users/albertpasto/), Thanks for this. You have noted a difference in the screen between the two documents. The document _tourdion_ contains a Revisions metabox (Registro de Revisiones) whereas _cantares_ does not. * This box is produced if the field post_content of the document is not empty. This field should contain the ID of the attachment post – that is, the PDF file itself. * If it is empty, then I would not expect you to be able to display a document. * If you have this data corruption, you could see the attachments in the Media library with attachment names like 7c30f7f466e79296d111ce60ec48690e.pdf. If you are able to see the attachment’s post_parent field, then this is the document to which it belongs. * If you have access to SQL, e.g. with PHPMyAdmin, then you can run this SQL: * `SELECT post_parent FROM`wp_posts` where post_type = ‘attachment’ AND post_parent IN (SELECT id FROM `wp_posts` where post_type = ‘document’ and post_content =”);` * I have used the standard wp_ as the table prefix. Yours may be different. * If you get any results, then for each result XXX in turn, run * `SELECT * FROM`wp_posts`where XXXX in (id, post_parent)` * If the post_content field of the document record is empty, then it needs to be set to the highest attachment id. * Regards, Neil James * Thread Starter [albertpasto](https://wordpress.org/support/users/albertpasto/) * (@albertpasto) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14944244) * please can you check the SQL statement (gives me error), there is some wrong symbol and i am not phpmyadmin expert thanks * Plugin Contributor [nwjames](https://wordpress.org/support/users/nwjames/) * (@nwjames) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14947546) * [@albertpasto](https://wordpress.org/support/users/albertpasto/). Apologies. I think that the issue aorise because the character used to start/end code within the replies here was used within the text: * ``` SELECT post_parent FROM wp_posts where post_type = ‘attachment’ AND post_parent IN (SELECT id FROM wp_posts where post_type = ‘document’ and post_content = ”); ``` * `SELECT * FROM wp_posts where XXXX in (id, post_parent)` * I have removed its use within the SQL statements itself. The highlighting should appear slightly differently. * Regards, Neil James * Plugin Contributor [nwjames](https://wordpress.org/support/users/nwjames/) * (@nwjames) * [4 years, 8 months ago](https://wordpress.org/support/topic/error-404-71/#post-14947580) * [@albertpasto](https://wordpress.org/support/users/albertpasto/), I tested copy/ paste into PHP