Thank you, all, for your kind responses. I am surprised by the friendliness of this community, pleasantly so! Naathim, I really appreciate your help, but unless you use a process different from that which the MBAM Customer Advocacy Specialists use to check key validity, I might not require your generously offered assistance! To clarify, I had purchased two lifetime licenses on Amazon a while ago, and created this forum post to try to feel out if I had been ripped-off or not, etc. before I tried using them. I had done a fair amount of reading, and found a lot of unhappy customers mentioning that their keys were invalid, among other things. I called MBAM support, and an EXTREMELY kind and patient Customer Advocate Specialist checked both licenses, and to my surprise and elation, they were both valid, according to him! This made my day, and removed a lot of stress from an otherwise stressful week. Thank you all, again. Hope you're all having a splendid day .