rescanning data base with out of date (old) charts takes for ever

[dominig]

With the release 3 of the plug in, on one of my PC (Linux OpenSUSE 43.1), equipped with official chart but out of renewal contract (18 moths old), if I try to make a DB rescan the system tells me that my PC configuration has changed and I need a new certificate.
The system takes for ever to scan the DB (a failing communication is tried for each individual charts files (having France, Spain, UK and Ireland, there is a lot of files).
If no charts scan is tried, system works fine telling that the chart or out of date for update.
Previous plugin version behaviour was more friendly.