Install File Commander

First: Download File Commander

On your tv box, open Chrome. Chrome can be found either on the main screen or under Apps/My Apps.
Don’t use Browser, it won’t let you open links. 

In Chrome, type in homearcadeinabox.com.
Go to the Login tab found in the top menu bar.
Login using the username and password you chose when you registered.

Go to the drop down under Download Pages called “Download Page B”.
*If you’ve logged in and can’t access Download Page B, you need to update Chrome.
Follow these instructions to update Chrome.

If the Home Arcade website is already open from a past update, refresh the page. At the bottom of the page you’ll see the download for File Commander. Click it to start downloading.

If you see the message “Chrome needs storage access to download files”, click Continue.

Allow any permissions.

Click Download if prompted.

Again allow any permissions.

Watch for a message telling you the file is downloading or was downloaded. It may flash by quickly. Give the download a minute to come in then click the home, back or escape button to return to the main screen.

Second: Install File Commander

Go to Apps.

Go to App Installer and click it. If your tv box doesn’t have App Installer, click File Browser.

For App Installer:

Click Local Disk
You should see File Commander there, click it
*If you don’t see File Commander there, it didn’t download, either because it needed more time to download or because your tv box has an older version of Chrome. Update Chrome as per the instructions above and allow more time for the download to come in.
Click Install
Click Open

Now File Commander is installed and you can use it to clear old files and old downloads. When you first open File Commander, you may see a pop up offering a free 7 day trial. Click the X in the top left corner of the pop up to close it.
Again, allow any permissions if asked.

Instructions on how to use File Commander to clear old files are here.

For File Browser:

Allow any permissions if asked
Click Local Disk
Scroll down to Download and click it
You should see file-commander-x-x-xxxx.apk there, click it.
*If you don’t see File Commander there, it didn’t download, either because it needed more time to download or because your tv box has an older version of Chrome. Update Chrome as per the instructions above and allow more time for the download to come in.

If you see a pop up that says, File Browser, For your security, your phone is not allowed to install unknown apps from this source, click Settings.
If you see another popup, click the first option, Install unknown app, com.android.tv.settings.
Then click Always.
A new menu will appear. Turn on all toggles.
If your tv box takes you to the install page automatically, click Install, then Open.
If it doesn’t automatically go to the install page, click back or escape to return to this page and click on file-commander-x-x-xxxx.apk again.

Click Install.
Click Open.

Now File Commander is installed and you can use it to clear old files and old downloads.
When you first open File Commander, you may see a pop up offering a free 7-day trial. Click the X in the top left corner of the pop-up to close it.
Again, allow any permissions if asked.

Instructions on how to use File Commander to clear old files are here.