How do I backup my MathCad product in case of failure or hacking of my computer?
Here's what I know, collabs correct where I miss.
First: Keep (a copy of) the installation CD in a safe place.
The remainder depends on the Mathcad product version:
If you have a single user license, using Cdilla, of mathcad versions 2001i to 15, you should make one full backup of the complete harddisk(-partition) where Mathcad is installed. There is a hidden Cdilla directory on the root of the drive(-partition) where Mathcad is installed. The info in the file is coupled to the drive/partition's serial number as assigned by Windows (that's not the serial number of the harddisk as assigned by the drive manufacturer!). Type 'vol' in a command prompt box to see that serial number, record it.
If you need to replace or reformat your harddisk make sure you restore all data and that the harddisk (partition) serial number matches that old number. Use VolumeId (SysInternals software) to set that serial number if needed. Mathcad should run, possibly after noticing and online correcting 'a problem with the license file'. If not: contact PTC if you have mathcad version above 11, if not: bad luck. (PTC ended support for Mathcad 11 and older).
Most other and newer (Prime) licenses use FlexLM. You need the license file, and the MAC address of your computer('s network interface card), because your license is (most probably) coupled to that address. The problem may be to find out to which (wired or wireless) network MAC address the license happens to be coupled. For versions above 11 you should be able to obtain PTC support.
Keep a copy of your sales order number and your license file. You may want to keep a copy of the installer too. The license is locked to the MAC ID of your primary network adapter, so if you switch PC you will need to get a new license from PTC. The best way to back up everything to protect against hard disk failure, serious malware (which is best avoided in the first place, by using decent anti-malware software!), etc is to image the disk. I highly recommend Macrium Reflect for that. It can even restore the image to a completely different hard drive, and everything works (even MC11, with it's Cdilla folder).
I've been downloading Mathcad update ZIP files (such as MED-60602-CD-150_M030.zip) to a separate download directory, in this case D:\Xfer-Win7\Mathcad\Mathcad15. When I backup my D drive, the saved Mathcad install files come along for the ride. It's also a good idea to keep copies of your user information, MAC address, and license files here too. I also make periodic C drive clones in case everything fails (e.g. a C drive failure). Be sure to write the date on the old C drive; I run from the cloned drive to reset the time to drive failure. I agree with all of the above comments.
I also noted that Mathcad only checks the first listed MAC address (this got me when I restored an update after I added a WiFi USB dongle and Mathcad would not accept my license file). If you have multiple NICs, Windows will list them in the order of UIC directory name (first digit only) via a registry key. Let a Mathcad service tech walk you through the setting if you need to change it.