A couple of days ago was online when I lost my WiFi connection. It's AT&T. Not u-verse. Straight from street. Had to call AT&T to reset. Reset went well. Back online. Was on my old iMac 2011. Totally erased. All files, folders, photos, calendar, history. Wiped clean. I have never heard of this happening before. My 2017 Mac is fine. Have changed all passwords. Anyone ever heard of this? Was it a glitch of some sort? Or malware? Do you think I could access files in safety mode? Time Machine, etc. all set up. Have not tried anything yet due to not knowing what happened.