I’ve seen this issue and actually re-created it just now in a GP 2018 test server I happened to have. Logged on as ‘sa’, I didn’t have anything showing on my Home page, nor was I able to add any of the sections of the Home page, including Quick Links or To Do.
Looking at the SY08100 table, which is the syHomePageLayout table, I only had 4 records for my user and all with a Visible value of 0, meaning not showing.
I then clicked on ‘Customize This Page…’, then in that window, at the bottom, click on ‘Change Role…’. You can select the same role or a different role, then save changes and click OK, which will re-launch the GP Home page, or may take you to the Intelligent Edge side. After this, you should be able to add and remove back the Quick Links and To Do sections of the GP Home page as you’d expect.
I did this and once I did, it showed the Home page sections as I’d expect, and the SY08100 table now showed 10 records for my user account, with some showing Visible = 1, meaning they’re showing on the Home page.
From prior testing, I believe the Quick Links is SectionID of 5, SEQNUMBR 1. In my case, originally, I didn’t even have this record in the SY08100 table, which is probably what you’re running into, thus you can’t add the section and have it show on the Home page.
Let us know if this works for you....
Thanks