Solved! Unfortunately, the process android.process.media has stopped

Some remedies are about the SD card, but I don't have an SD card. Here is what I did:

1. Navigate to Settings, Accounts, and Google.
2. Move all of the toggles to “Off.”
3. Navigate to Settings, Storage &USB.
4. Tap “Cached Data” and then “OK.”
5. Navigate to Settings, Application Manager, and then Downloads.
6. Select “Downloads” and select “Force Stop.”
7. Turn off your phone for a couple of minutes. Remove the battery if it's not sealed
8. Switch your device on once more and wait until it has finished booting back up.
9. Navigate to Settings, Accounts, and Google.
10. Move all of the toggles to “On” to allow syncing again.

Solved! 100 percent disk usage in Windows 10 after a big rearrange of files

I have a lot of PDF's and word docs in many many folders. Today I mucked around with my file structure.

Then my whole computer froze, and took a few reboots to heal itself.

I think too many processes were dominating the disk at the same time:

1. Crashplan backup started running (it had to do a massive new backup because of what I did)
2. I also have a local file backup app called Argentum that also started running
3. Windows Search started reindexing

And so when I innocently opened File Explorer in the midst of all this, the computer crashed.

I found some background by googling. I learned that when the hard drive is constantly working at 100%, there's no spare capacity to perform other tasks, even routine operating system tasks, such as opening task manager. This can slow everything to a halt, making the computer completely unresponsive.

I also learned this is a common problem in Windows 10.

It's easy to solve, though. After doing a big file re-org, best to let just one backup program run at a time (either Crashplan or Argentum in my case) and temporarily disable the other one. And leave the computer alone for a little while.