Hello I am not a security professional. I run a business from home with two desktop computers. They both run Windows 7. Mostly they don't form a network except when I use a wireless transducer. The main internet is ethernet. Anyway, I need a plan of backups in case I get hit by cryptolocker or something just as nasty. I have: two external hard disk drives, paragon installed on both computers, and antivirus on both computers - Kaspersky on one and avast and malwarebytes on the other. Thus I don't know the following: - how often should I backup to my external hard drives? Too soon and the external backup could become useless due to also being malwared. Too seldom and I could risk not having backed up a ,lot of recent business documents. - anything else that I should do? Thank you. p.s I don't know if this is the right thread. If not please move it to a better one.