Title: Invalid backend response. ??? empty Last modified: August 31, 2016 --- # Invalid backend response. ??? empty * Resolved [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 2 months ago](https://wordpress.org/support/topic/invalid-backend-response-empty/) * I am attempting to upload a file either by the ‘File manager’ menubar or by drag and drop. * I am getting the error message: “Invalid backend response. ??? empty”. The ??? refers to the fact that the error message is obscured by an exclamation point icon overlaying the message…very handy. * I have verified via my Transmit FTP client that the folder I am attempting to upload to has 755 permissions. * I am able to create, rename and delete folders (and text files) via the ‘File Manager’ menubar, I just cannot upload any files. * [https://wordpress.org/plugins/file-manager/](https://wordpress.org/plugins/file-manager/) Viewing 15 replies - 1 through 15 (of 15 total) * Moderator [Jan Dembowski](https://wordpress.org/support/users/jdembowski/) * (@jdembowski) * Forum Moderator and Brute Squad * [10 years, 2 months ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255463) * Please excuse me [@dpotter2](https://wordpress.org/support/users/dpotter2/) while I go off topic with the plugin author for a minute. * Hi [@aihimel](https://wordpress.org/support/users/aihimel/) I’ve deleted your offer to login to your user’s site. I’m am 100% sure you mean well but please _never ask for credentials on these forums._ * [http://codex.wordpress.org/Forum_Welcome#The_Bad_Stuff](http://codex.wordpress.org/Forum_Welcome#The_Bad_Stuff) * Now for the why: The internet is a wonderful place full of very nice people and a few very bad ones. I’m sure everyone here is very nice however, by giving some ones keys to your house you are trusting they wont steal anything. Likewise the person who takes the keys is now responsible for the house FOREVER. * If something was to go wrong, then you the author may well legally become liable for damages, which they would not normally have been as their software is provided without warranty. * Please be aware that repeatedly asking for credentials will result in us asking you to repeatedly stop before escalating up to the plugins team. * Plugin Contributor [Aftabul Islam](https://wordpress.org/support/users/aihimel/) * (@aihimel) * [10 years, 2 months ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255464) * Hello Jan Dembowski, * I am sorry for that unexpected post asking website credentials. I will not ask for website credentials in future. * Thanks Aftabul Islam * Moderator [Jan Dembowski](https://wordpress.org/support/users/jdembowski/) * (@jdembowski) * Forum Moderator and Brute Squad * [10 years, 2 months ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255465) * Thank you for understanding. 😉 * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255494) * Hello Aftabul, * Any thoughts on the “Invalid backend response ??? empty” error when trying to upload files? * Don * Plugin Contributor [Aftabul Islam](https://wordpress.org/support/users/aihimel/) * (@aihimel) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255499) * **[@dpotter2](https://wordpress.org/support/users/dpotter2/)** Could you please tell me what type of file you are trying to upload and what is the size of your file. * Thanks Aftabul Islam * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255511) * ok, it appears the problem is limited to .jpg and .png files. * .zip, .txt,.pdf, and .docx files are ok. * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255512) * The jpg file I tried was 149kb and the png is 454kb * Plugin Contributor [Aftabul Islam](https://wordpress.org/support/users/aihimel/) * (@aihimel) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255513) * **[@dpotter2](https://wordpress.org/support/users/dpotter2/)** * I have tested the .png and .jpg upload on my server. It is working fine. * Can you see any error on your browser console while uploading those images? * Thanks Aftabbul Islam * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255526) * In Safari console: * elfinder debug: [error] [file-manager-wrapper] – “Invalid backend response. Data is empty.” (elfinder.full.js, line 4676) * Plugin Contributor [Aftabul Islam](https://wordpress.org/support/users/aihimel/) * (@aihimel) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255530) * **[@dpotter2](https://wordpress.org/support/users/dpotter2/)** * Could you answer the following questions: * + What is your safari version? * + PHP version? * + Do you have Mogrify / GD / Imagic module installed on your server? * + Did you tried with other browsers like Google Chrome / Chromium, Firefox or Opera? * Thanks Aftabul Islam * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255537) * I am running Safari 9.0.3 * The hosting company (Flywheel) says the server is running PHP 5.5 with the GD and Imagick module enabled. They say they are happy to help with any troubleshooting steps as necessary. * And yes, I did try Chrome version 49.0.2623.112 with the same result. * I did turn on WP_Debug mode and noticed that when I attempted to upload a jpg or png, the error message changed to “not json”, when I turned off WP_Debug, the message returned to “Data is empty”. * If it will be of any help I can email the server log files. * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255559) * Any further ideas? * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255567) * If I rename or remove the file extension on the .jpg or .png files, they will upload with no problem. Of course I don’t wish to do that. * Plugin Contributor [Aftabul Islam](https://wordpress.org/support/users/aihimel/) * (@aihimel) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255575) * **[@dpotter2](https://wordpress.org/support/users/dpotter2/)** * Hi, * It is working strangely. I can’t figure out why it is acting like this way. I will run further test on the plugin and will try to understand what is the problem. * Thanks Aftabul Islam * Thread Starter [dpotter2](https://wordpress.org/support/users/dpotter2/) * (@dpotter2) * [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255578) * I migrated the entire site to another development server (different hosting company) and the plugin works fine. I contacted the hosting company for the production server (flywheel) and they responded: * “I watched the error logs when trying to upload the files and nothing is being thrown at the server level. I don’t think this is a server related issue as much as a problem with the plugin and they way it is trying to communicate with our server, but unfortunately I don’t have any logs from the plugin to look at and that would need to be something the plugin developer should look at since we wouldn’t be familiar with their code.” Viewing 15 replies - 1 through 15 (of 15 total) The topic ‘Invalid backend response. ??? empty’ is closed to new replies. * ![](https://s.w.org/plugins/geopattern-icon/file-manager_e5f2f9.svg) * [File Manager](https://wordpress.org/plugins/file-manager/) * [Frequently Asked Questions](https://wordpress.org/plugins/file-manager/#faq) * [Support Threads](https://wordpress.org/support/plugin/file-manager/) * [Active Topics](https://wordpress.org/support/plugin/file-manager/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/file-manager/unresolved/) * [Reviews](https://wordpress.org/support/plugin/file-manager/reviews/) * 15 replies * 3 participants * Last reply from: [dpotter2](https://wordpress.org/support/users/dpotter2/) * Last activity: [10 years, 1 month ago](https://wordpress.org/support/topic/invalid-backend-response-empty/#post-7255578) * Status: resolved