I thought this was a good idea as I didn't think my WSUS / SUP configuration was working after upgrading the Server from 2008 R2 to 2012 R2. I reinstalled WSUS and SUP as below, but what I should've done first was check the Microsoft Configuration Manager/Logs WCM.log and wsyncmgr.log files, these would've shown that there was an error with searching for Adobe updates, which are no longer supported on WSUS 4.0, so couldn't be removed (except by changing a single value in SQL Server).
Anyway, not knowing that I decided to reinstall the Software Update Point and WSUS Roles to hopefully get things running again. This is a a full reinstall, so WSUS will need to re-download 30-40GB of data, and the SUP will need to do a lot of processing to understand the client update status.
- Snapshot VM
- Remove SUP from SCCM Management Console. Administrator > Sites > Select Site Server > Right click, Remove Role
- Remove WSUS Role. Server Manager > Remove Roles and Features > Untick Windows Server Update Services (WSUS) Reboot Server afterwards
- Remove SUSDB. Open SQL Management Studio, find SUSDB, right click, Delete.
- Remove old WSUS Content Folder. (find location using Regedit HKLM\software\Microsoft\updateservices)
- Reboot Server for good measure
I then followed these excellent in-depth instructions to set up the server again: https://everythingsccm.com/2017/03/27/configuring-wsus-with-sccm-current-branch-server-2016-part-i/
This link which I found after I did the reinstall has a more in-depth way to reinstall WSUS/SUP, as well as their solution for the updating the erroneous SUP classifications