when a threat is found on software does that make the software unusable?

Hi AntoniaLitwak
 
Welcome to the Community Forums.
 
Generally speaking that is the case because either WSA completely removes the application that is considered to be malware or it may quarantine part of the application...in either case the applicaiton would generally be unusable.
 
However, if quarantined and you decide that the application is 'clean' and you restore the quarantined components then the application will be usable again. Having said that one should of course be very careful about doingsuch a thing in case one is incorrect and the application is in fact not clean.
 
Also, occassionally WSA will fall foul of False Positives, i.e., its determination of malware will be incorrect. This does happen sometimes, though rarely in my experience, but again here most likely the application concerned will no longer work for one of the reasons previously advised.
 
Hope that helps?
 
Regards, Baldrick