Subject: Cisco ISR4331 Router Firmware Upgrade Failure 21 Feb 2025 Friday Good day from Singapore, I have used the following guide to upgrade the firmware of my Cisco ISR 4331 router. Reference Guide: Upgrade Firmware on Cisco Devices (Step-by-Step Guide) Link: https://appuals.com/upgrade-firmware-cisco-devices/ I was trying to upgrade the firmware from isr4300-universalk9.03.16.10.S.155-3.S10-ext.SPA.bin to isr4300-universalk9.17.12.04a.SPA.bin. In the course of upgrading the firmware, I have executed the following command. boot system flash isr4300-universalk9.17.12.04a.SPA.bin I have also executed "write memory". However, after rebooting my Cisco ISR 4331 router, I get the following errors: [CODE] unable to open bootflash:/isr4300-universalk9.03.16.10.S.155-3.S10-ext.SPA.bin (14) ........ autoboot: boot failed, restarting... Resetting ....... [/CODE] Do I need to break into ROMMON and edit the startup configuration file? Please advise. Thank you. Regards, Mr. Turritopsis D...