I recently re-installed Freelancer (on Win10).
This was my recipe:
a. Freelancer clean install
b. MS patch v1.1
c. Jason FLP - (the unofficial 1.4 patch and other fixes)
d. Installed the no-cd exe
Vanilla Freelancer played perfectly online. I found that the single player campaign did not.
When I came to try the Discover mod, it did not like my “fixed” vanilla Freelancer install.
So, I simply uninstalled Freelancer, re-installed it again, applied the MS v1.1 patch (cos I wanted it to be totally MS up to date).
Then I ran the Discover installer and it installed first time. Make sure you run the Discovery installer with admin rights.
Been playing it without a hitch for a week now.
Ping me if you need more details…
Jerico