I read somewhere on this forum that one should always have two backups on two separate and different external destinations so I was looking for a second............I suppose I could create another set of folder-pairs in SyncToy with a different destination - the SD card - but I wasn't sure if that would work out.
Yeah, I'd say backups to 2 different destinations is sound.
My Windows installation isn't critical---if it failed and my Macrium image backup of it failed, I'd easily survive. I'd just have to spend the hours necessary to reinstall and reconfigure. So I personally don't use 2 different imaging programs to backup Windows. Just Macrium, and I keep the most recent 2 monthly images.
Data IS critical, so I back up multiple ways:
1: Primary backup to a second entirely separate internal drive, using FreeFileSync, at least daily. This backs up 100% of my data.
2: Backup of my most critical data files to a USB flash drive by simple drag and drop copy. Once a month. Maybe I should do this more often. They don't amount to over 11 GB right now. Mostly pictures, Word files, and Excel files. Pretty much everything I have other than video, mp3s, images of C, and downloaded programs----all of which could be replaced or not missed.
3: Backup of ALL data, but by simple drag and drop copy to a separate internal drive mounted in an external dock. I use an older retired drive that at one time held my OS before I switched to an SSD. I do this quarterly. Maybe I should do this more often.
4: Backup of ALL data to the same drive mentioned in step 1, but using simple drag and drop copy rather than FreeFileSync. I do this quarterly, but not on the same quarterly schedule that I use in step 3.
I haven't lost anything yet.
I'm taking a risk in that I don't have anything backed up offsite and that continually nags at me. I could be screwed in a total fire loss or a thorough theft. I categorically refuse to use cloud storage.
You just have to come to a conclusion about what's of value and the time and money you are willing to spend to protect it.