Never open a Zip file attached to an email unless you already know what it is and you were expecting it.
These emails commonly look like they are from couriers like UPS, USPS, FedEx, Australia Post and others. Sometimes they will appear to be a lawyer requesting your appearance in court. Another common occurrence appears to be an invoice from Amazon.
Beware of everything you don’t clearly recognise as someone you already know.
CryptoLocker (and its many variants) will attack and encrypt files on local, external (USB) and network drives. If your backup is a copy of files stored in one or more of these locations then your whole backup regime may have just been rendered useless. Affected files will include many types of documents such as Word, Excel, PDF and also photos. Give us a call to discuss a more appropriate backup solution.