Error 1603 generates a 404 error

I am experiencing the EXACT same problem. 
AND I have tried a manual install! 

But first, let's talk about the 1st annoying bug. Like the OP, I too see the Update Failed message with the "Details" link. When I click that link, I am also taken to a 404 Error page! Why?

All my Cloud Apps except the Adobe Acrobat are updating without issues. Now, Acrobat is so far behind in updates, it is beginning to warn me that I'll be locked out of the app for not updating. 

Incidentally, I did manage to locate the error message and I tried every potential solution. I still cannot update Acrobat!

Furthermore, I am really disappointed with the one official Adobe response from AkanchhaS.
Seriously? That is the extent of your assistance. We pay a LOT of money for the Adobe Cloud suite and I think we deserve a bit better service. 😞
1. Your support is inadequate and kind of dismissive.

2. Your suggestion to download the patch from here- https://www.adobe.com/devnet-docs/acrobatetk/tools/ReleaseNotesDC/index.html  - is completely useless because this is just a history of release notes... 100's of release notes. Where is the patch you speak of?
3. Had you done a little research, you should have pointed icanopit  to the correct page that covers the error (see my link, above). 
4. Another suggestion you failed to mention is to uninstall Adobe Acrobat and reinstall. Sometimes through no specific fault of an application, files become corrupted. It's the nature of computers! Anyhow, that is my next step to solve this long-annoying problem. 

Hi @icanopit 

Hope you are doing well.

Seems the auto-update is getting failed in between the process. Could you please try installing the update manually-

1- First, close the application and its processes from the task manager

2- Once done, open Acrobat >help>install update

3- else, download the patch from here- https://www.adobe.com/devnet-docs/acrobatetk/tools/ReleaseNotesDC/index.html 

Let us know if it still doesn't work.

Thanks,

Akanchha