The storage views tab in the vSphere client disappeared, and vCenter System Services displayed some of the following errors:
As soon as OfficeScan had finished uninstalling, the assortment of errors in System Services went away and the Storage Views tab worked. (No need to restart services/reboot)
This was a test to see if the kb article would fix it, so I wasn't about to leave vCenter with no AV. I re-installed OfficeScan, and the errors didn't re-appear.
So the fix was to uninstall/re-install OfficeScan.
TrendMicro support suggested to disable the OfficeScan client services one at time to identify which one is causing the conflict.
Kindly configure the Privileges and Other Settings for the VCenter server in the OfficeScan web console page under Networked Computer>Client Management. Then under Other tab, please uncheck Protect client services.
Then stop the services for the OfficeScan client in the Vcenter server. Then start one service at a time to isolate this.
• OfficeScan NT Listener (TmListen.exe)
• OfficeScan NT RealTime Scan (NTRtScan.exe) • OfficeScan NT Proxy Service (TmProxy.exe) • OfficeScan NT Firewall (TmPfw.exe); if the firewall was enabled during installation • Trend Micro Unauthorized Change Prevention Service (TMBMSRV.exe)
Although they got back to me pretty quickly, I'd already uninstalled/re-installed OfficeScan, and now i'm unable to replicate the problem, but something to try if it happens again.