[AT&T Samsung Galaxy S 4 General] lexridge:
I appreciate you help, and yes I know how finicky USB cables/ports can be. I am using the same computers and cables which work fine with both my Galaxy S3 and my S5 using Odin. Weird! This is not like its my first rodeo with Odin. I have been flashing phones for years. This is the first time I have ever had such problems! I am really starting to wonder if this Galaxy S4 has some problem, or is locked down tighter than most.

Here is dmesg from Linux

Aug 23 20:53:47 garage kernel: [28193.103549] cdc_acm 4-1.4.4:1.0: failed to set dtr/rts
Aug 23 20:53:47 garage kernel: cdc_acm 4-1.4.4:1.0: failed to set dtr/rts
Aug 23 20:53:47 garage ModemManager[862]: <info> Creating modem with plugin 'Generic' and '1' ports
Aug 23 20:53:47 garage ModemManager[862]: <warn> Could not grab port (tty/ttyACM0): 'Cannot add port 'tty/ttyACM0', unhandled serial type'
Aug 23 20:53:47 garage ModemManager[862]: <warn> Couldn't create modem for device at '/sys/devices/pci0000:00/0000:00:13.2/usb4/4-1/4-1.4/4-1.4.4': Failed to find primary AT port
Aug 23 20:54:00 garage kernel: [28206.658773] usb 4-1.4.4: USB disconnect, device number 34
Aug 23 20:54:00 garage kernel: usb 4-1.4.4: USB disconnect, device number 34
Aug 23 20:54:00 garage ModemManager[862]: <info> (tty/ttyACM0): released by modem /sys/devices/pci0000:00/0000:00:13.2/usb4/4-1/4-1.4/4-1.4.4
Aug 23 20:54:00 garage systemd-udevd: error opening USB device 'descriptors' file
Aug 23 20:54:01 garage kernel: [28206.835962] usb 4-1.4.4: new full-speed USB device number 35 using ehci-pci
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: new full-speed USB device number 35 using ehci-pci
Aug 23 20:54:01 garage kernel: [28206.910395] usb 4-1.4.4: not running at top speed; connect to a high speed hub
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: not running at top speed; connect to a high speed hub
Aug 23 20:54:01 garage kernel: [28206.911595] usb 4-1.4.4: New USB device found, idVendor=04e8, idProduct=685d
Aug 23 20:54:01 garage kernel: [28206.911601] usb 4-1.4.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 23 20:54:01 garage kernel: [28206.911606] usb 4-1.4.4: Product: MSM8960
Aug 23 20:54:01 garage kernel: [28206.911610] usb 4-1.4.4: Manufacturer: Sasmsung
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: New USB device found, idVendor=04e8, idProduct=685d
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 23 20:54:01 garage kernel: [28206.912548] cdc_acm 4-1.4.4:1.0: ttyACM0: USB ACM device
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: Product: MSM8960
Aug 23 20:54:01 garage kernel: usb 4-1.4.4: Manufacturer: Sasmsung
Aug 23 20:54:01 garage kernel: cdc_acm 4-1.4.4:1.0: ttyACM0: USB ACM device
Aug 23 20:54:01 garage mtp-probe: checking bus 4, device 35: "/sys/devices/pci0000:00/0000:00:13.2/usb4/4-1/4-1.4/4-1.4.4"
Aug 23 20:54:01 garage mtp-probe: bus: 4, device: 35 was not an MTP device
Aug 23 20:54:16 garage ModemManager[862]: <info> Creating modem with plugin 'Generic' and '1' ports
Aug 23 20:54:16 garage ModemManager[862]: <warn> Could not grab port (tty/ttyACM0): 'Cannot add port 'tty/ttyACM0', unhandled serial type'
Aug 23 20:54:16 garage ModemManager[862]: <warn> Couldn't create modem for device at '/sys/devices/pci0000:00/0000:00:13.2/usb4/4-1/4-1.4/4-1.4.4': Failed to find primary AT port

Also, the download bar actually does appear on the phone when I start the Odin process, but never proceeds any further. So it IS finding it.

EDIT: Could this all be because there is no SIM card installed?

EDIT2: I tried to update using the OTA file I found using the ADB update method, and it failed on a corrupt file /system/bin/ddexe. I re-rooted the device and discovered there was also a /system/bin/ddexe_orig file, which I moved back to ddexe. Tried the adb update again, and viola!! It worked! I am now on 4.4.2. Now lets see if I can get to 4.4.4 then 5.01.

EDIT3: All the other updates also went in fine. It's now running OC4 stock non-rooted.