'Some' anti spyware programs & surprisingly some major companies of adopted such, are designed 'against' p2p sharing programs despite they do not have spyware. Thus, answer for future is to put LW on the safe list, else don't run it or look for an alternative & there are many other alternatives that are safe to run with LW. A list of safe ones we recommend are here WARNING: Viruses on network you should be aware of! (click on blue link) though there are also others out there that are safe with LW & do a good job.

Answer? Reinstall.

LW Pro support lasts 6 months, so you will have an email from them with a link to your personal download page. Check it & then bookmark that page.
If you never received any such email then you probably did not purchase pro from the official site but perhaps a scam site that gave you a link to the LW basic version.