Android Studio: Error parsing XML & URI is not registered
I was having a similar issue. However, the comments did not assist me in the solution to this issue. This answer from this question actually solved my problem.
Summary:
Go to "File > Project Structure > Modules", click "add" and then click "android" and "apply/ok". That should solve anyone having a similar problem but the comments for this question are not helping you.
For me, the problem occured when I created my own subfolder for old code.
Specifically, Android Studio threw an error for all layout files that weren't in the default folder ../res/drawable/, but instead placed in my own subfolder ../res/drawable/backup.
I got the same error for a long time and none of the answers I found online really helped me, or probably I wasn't looking the right way. At the end what I found out was the way I named the directory. So, I was trying to make the landscape layout for my app and named it layout_land. That kept showing me the URI is not registered error. I just had to change the directory name to layout-land.
Summary: No underscores in directory names!