This error can be caused by another Security\/Unknown software or even missing installation files when the product is being updated or upgraded to a newer version.\r\nFix Norton Error 8504, 104 on Windows 7, 8, & 10\r\nAnyone can Solve Norton Error 8504, 104 on Windows\u00a0Computer by following simple steps.\r\n1.\u00a0 Run Norton Remove & Reinstall Tool\r\nThis is the most important Troubleshooting step and is most likely going to solve all Norton Errors in the first attempt.\r\n\r\nIf you are using Norton Family installed, we advice that you uninstall it before you run the Norton Remove and Reinstall tool from Control Panel.\r\n\r\n\r\n \tDownload the\u00a0Norton Remove and Reinstall\u00a0tool.\r\n \tSave the file on the desktop and click on\u00a0NRnR\u00a0icon.\r\n\r\nOn some browsers, the file is automatically saved to its default location which is Downloads or Documents.\r\n\r\n \tAgree with Terms and Follow all the Instructions to complete the Installation.\r\n \tClick on Advanced Options.\u00a0\r\n \tSelect Remove Only and Click Remove\r\n \tClick Restart when prompted.\r\n \tAfter computer Restarts, Follow the\u00a0On-Screen Instructions to reinstall Norton.\r\n\r\n2. Remove Non-Symantec Security or Unknown Softwares.\r\nYou can simplify removal of Non-Symantec products or Unknown software that most of the times create software conflicts by downloading our favorite Uninstaller from Iobit.\u00a0\r\n\r\nYou will not only be able to remove software from your computer but also remove registry entries created by that software during the of installation or while in use.\r\n\r\nIf you are good with troubleshooting computer problems on your own and identifying\u00a0whether any software installed on your computer is good or bad by verifying the publisher authority, remove them manually by;\r\n\r\n \tGoing to Control Panel and open Programs and Features\r\n\r\nOr\u00a0Press the\u00a0Windows\u00a0+\u00a0R\u00a0keys to open the Run dialog box. and type\r\n\r\nappwiz.cpl\r\n\r\n \tIn the list of currently installed programs, select the non-Symantec security product, and then click\u00a0Uninstall\u00a0or\u00a0Remove.\r\n \tAlso,\u00a0remove Softwares from Unknown publishers.\r\n\r\n3. Update Graphics and other System Drivers.\r\nIt's important to have all the system drivers up to date (Graphics Driver most importantly) in order to smoothly run any software installed on the Windows operating system.\u00a0We recommend that you download one of our handpicked Free driver updater tools to minimize the effort or you can manually update the drivers by following the instructions below;\r\n\r\n \tPress the\u00a0Windows\u00a0+\u00a0R\u00a0keys, to open the\u00a0Run\u00a0dialog box.\r\n\r\nType in the following text, and then press\u00a0Enter. \r\n\r\ndevmgmt.msc\r\n\r\n \tIn the\u00a0Device Manager\u00a0window, double-click on\u00a0Display adapters.\r\n \tRight-click on the HD graphics card, and select\u00a0Properties.\r\n \tOn the\u00a0Driver\u00a0tab, check whether the graphics card driver is outdated or current.\r\n\r\nIf the driver is outdated, you need to download the latest update and install the latest version of the graphics card driver.\r\n\r\n \tYou can either use the Free Driver Updater Tool or Select your graphics card manufacturer and download the driver to install manually:\r\n\r\nAMD\/ATI Radeon HD video graphics\r\n\r\nIntel HD video graphics\r\n\r\nNVIDIA graphics\r\n\r\n\r\n\r\n \tCheck others drivers that might require an update.\r\n \tRestart your computer and start Norton to check if the issue has been resolved.\r\n\r\nThat's\u00a0it.\r\nLet us know in the comments below if you are still getting an error pertaining to Norton.