Start Virtuoso using 'layoutPlus' or use the 'Launch > Layout XL' toolbar pulldown. The application Title Bar should indicate 'layoutPlus'. When launched it will bring up both the schematic and layout windows. If it doesn't come up you may not be licensed for XL and should get a message indicating this.
You can also check your license file for the license key strings 'Virtuoso_Layout_Suite_XL' and 'Virtuoso_Schematic_Editor_XL'.
Reference Chap 1. ''Getting Started with Layout XL' in the reference manual I indicated in my previous response on how to start using LayoutPlus.
Use of connectivity and the XLProbe function will also be dependant on correct data modeling (e.g. instance, terms, pins, etc.) and connections done in the layout. If you did the original layout in VLS L the results may need to be modified for a correct connectivity use model.
For further assistance please contact Cadence Customer Support or your local Field AE.
Sr. Technical Leader
Technical Field Operations, North America-Central Region