If the WLC is bricked (boot loop or missing OS), you must use or TFTP at the bootloader :
If your GUI times out after 90 seconds, the TFTP transfer failed. The 2504 web server is single-threaded; large firmware files require FTP . Switch to FTP if the GUI freezes. cisco wlc 2504 firmware download work
If the WLC is bricked (boot loop or missing OS), you must use or TFTP at the bootloader :
If your GUI times out after 90 seconds, the TFTP transfer failed. The 2504 web server is single-threaded; large firmware files require FTP . Switch to FTP if the GUI freezes.