Is it possible to enable System Protection from the command prompt?

Update May 2022:

Even though I wrote this for fixing an issue with Windows 8.1, others have found that it also works for more recent versions of Windows (up to Windows 11 so far). If you happen to be the first person to try this with a newer version of Windows, please comment on whether or not it worked.

Looking at a an article for Windows 7 about the same issue, I found a suggestion to use the following command:

Rstrui.exe /offline:C:\windows=active

Rstrui.exe opens up the system restore window. I'm not sure what the argument means, but it made it so I could actually use the restore points! Yay!

Unfortunately, this did not completely fix my problem - the system restore failed. The error message implied that it had something to do with the registry. So, using the command prompt I went into C:\Windows\System32\config and renamed two of the registry files:

ren SYSTEM system.001
ren SOFTWARE software.001

After doing this, I ran the system restore again (using the same argument as I did the first time) and it worked! I was able to log back into my computer!