Launcher error

Hello. The new launcher that went live for 5.1 isn't working for me. Every time I try it launches a small internal window that displays the following:

An error has occurred on this page

Line: 1
Char: 1
Error: Invalid character
Code: 0
URL: https://launcher.finalfantasyxiv.com/v510/polyfill-53c72c289d6986af35ba.bundle.js

(I have elected to disable the autolinking feature as I'm somewhat afraid that posting it may trip a bot of some sort)

it then asks if I want to continue via a yes/no prompt. No matter which is chosen it repeats 5 times and then will hang on the ff14 online logo indefinitely.

I should note that the launcher worked correctly the first time but shortly after my pc suddenly rebooted before I could do anything. Thereafter all of my attempts result in the above error code. I have attempted to reinstall the game but i get the same errors. I run the Steam version of the game. My specs are listed below

CPU: AMD Ryzen 2600x
GPU: AMD Radeon RX 580 8gb
RAM: 16gb @ 3000mhz
storage: m.2 ssd 512gb, 2 2tb hdd

Thank you for taking the time to help in advance

Good morning and thank you for posting on the Final Fantasy XIV Technical Support Forums.

This is usually the result of the cache and security settings in the Internet Explorer Web browser. The game will use Internet Explorer to connect to the internet.

Open Internet Explorer, then open the "Tools" setting, go to "Internet Options" and adjust the following settings:
- Under the "General" tab, please delete ALL browser history.
- Under the "Security" tab, please move the slider to the lowest possible settings or no higher than "Medium"
- Under the "Privacy" tab, click “Advanced” and select ‘Accept’ under both First Party and Third Party Cookies.
- Under the "Advanced" tab, please make sure that "Allow software to run or install even if signature is invalid" is CHECKED.
- Make sure that all SSL and TLS (EXCEPT SSL 3.0) are CHECKED. [SSL 3.0 should be UNCHECKED]
- Hit "Apply" to save the settings, and then "OK, to close the Internet Options menu.
- Right-Click on the FFXIV launcher icon and select "Properties"
- Go to the "Compatibility" tab, and change the compatibility mode to "Windows 7"
- Hit "Apply", then "OK" to save the changes.
- Please RESTART your PC now. Once your PC has been restarted, Right-Click the FFXIV launcher icon once more and select "Run as Administrator"

We hope we can be of assistance in helping you enjoy the exciting world of Final Fantasy XIV!