Title: installation issue Last modified: August 31, 2016 --- # installation issue * [rudtek2](https://wordpress.org/support/users/rudtek2/) * (@rudtek2) * [10 years, 4 months ago](https://wordpress.org/support/topic/installation-issue-44/) * When i installed this plugin i got this error: * The plugin generated 878 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin. * what does that mean? * [https://wordpress.org/plugins/ultimate-product-catalogue/](https://wordpress.org/plugins/ultimate-product-catalogue/) Viewing 2 replies - 1 through 2 (of 2 total) * Thread Starter [rudtek2](https://wordpress.org/support/users/rudtek2/) * (@rudtek2) * [10 years, 4 months ago](https://wordpress.org/support/topic/installation-issue-44/#post-6945212) * in the settings page it says this: * Notice: Use of undefined constant php – assumed ‘php’ in /home/sss/public_html/ test/wp-content/plugins/ultimate-product-catalogue/html/DashboardPage.php on line 31 * Plugin Author [Rustaurius](https://wordpress.org/support/users/rustaurius/) * (@rustaurius) * [10 years, 3 months ago](https://wordpress.org/support/topic/installation-issue-44/#post-6945507) * Hi rudtek, * It sounds like there might have been a corrupted or missing file when the plugin package was downloaded. Could you try deleting the plugin and re-installing? * The notice shouldn’t be an issue; if there are PHP errors or warnings, those can cause problems, but notices just let you know when there are small typing errors in the code. In this case, there’s a space missing between the opening