Q: Can't download SMC firmware update 1.8. Help!

My battery stopped charging completely in my Macbook Pro mid 2012 awhile ago. I realized there was an update (SMC firmware update 1.8), and made many attempts to download it. My computer has a few viruses. I eventually was able to, but in the middle of downloading, right when the computer shut down and was getting ready to reboot, I accidentally unplugged the power cord. When I restarted the computer, the firmware update was not installed.

Now when I try and install the update, it just says "Software not supported by this system." I can't install it at all.

The disc drive is broken too, and I think there was an update for that. It was an update describing fixing an issue regarding shutting down during heavy processing loads, but it just says the same thing.

What can I do?