Error downgrading to kitkat 4.4.2 from lollipop 5.1.1 [SM-G900A]

[xlostprodigy]

model number: SM-G900A

I followed this tutorial from another thread but it has yet to work and gives me the following error:

Thread:

forums.androidcentral.com/samsung-galaxy-s5/489071-tutorial-downgrade-samsung-galaxy-s5-5-0-4-4-kitkat.html

error message from odin:

<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> G900AUCU1ANCE_G900AATT1ANCE_G900AUCU1ANCE_HOME.tar.md5 is valid.
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<ID:0/004> Added!!
<ID:0/004> Odin v.3 engine (ID:4)..
<ID:0/004> File analysis..
<ID:0/004> SetupConnection..
<ID:0/004> Initialzation..
<ID:0/004> Get PIT for mapping..
<ID:0/004> Firmware update start..
<ID:0/004> SingleDownload.
<ID:0/004> aboot.mbn
<ID:0/004> NAND Write Start!!
<ID:0/004> FAIL! (Auth)
<ID:0/004>
<ID:0/004> Complete(Write) operation failed.
<OSM> All threads completed. (succeed 0 / failed 1)

If anyone knows how I can fix this error let me know. Thanks!