After uninstall Service Catalog 17.3 and RU11 patches, sometimes when you install SC 17.3 back and you may see nothing is really installed--the windows programs window does not display it and the install UI does not seem to install it. This techdoc explains what you could do to make it possible to install again.
Release : 17.3
Component : Catalog - Install
If the mdb table al_cdb_componentinstallstate has this packageid
completed, you can follow these steps to install it
1. have a machine backup for both SC and mdb( so you can roll back whenever it is needed)
2. back up mdb table al_cdb_componentinstallstate
3. delete the row with packageid is task.slcm.patch.binaries.18.104.22.168 from table mentioned in step 2.
4. install SC RU11 from the installation media