Windows 8.1 login error after power cut "The object invoked has discoected from its client"

Earlier I had a power cut, possibly due to weather. My PC was powered on and logged in but locked at the time, and when I tued it back on later, trying to log in resulted in the error message "The object invoked has discoected from its client." with the option only to try logging in again. I booted into Safe Mode and I can log in properly that way, but I'm suspecting a storage or memory failure. What most likely happened? And how could I fix it, hopefully without restoring anything?